DPP SOLUTION

• Subject - Physics

• Chapter – Newton's Laws of Motion

DPP’s-PPT’s By- Aayudh Sir

 Question

A rider on horse back falls when horse starts running all of a sudden because

1 Rider is taken back

2 Rider is suddenly afraid of falling

3 Inertia of rest keeps the upper part of body at rest whereas lower part of
the body moves forward with the horse

4 None of the above

Ans (3)
 Question

When a train stops suddenly, passengers in the running train feel an instant jerk
in the forward direction because

1 The back of seat suddenly pushes the passengers forward

2 Inertia of rest stops the train and takes the body forward

3 Upper part of the body continues to be in the state of motion whereas the
lower part of the body in contact with seat remains at rest

4 Nothing can be said due to insufficient data

Ans (3)
 Question

A man getting down a running bus falls forward because

1 Due to inertia of rest, road is left behind and man reaches forward

2 Due to inertia of motion upper part of body continues to be in motion in

forward direction while feet come to rest as soon as they touch the road

3 He leans forward as a matter of habit

4 Of the combined effect of all the three factors stated in (1), (2) and (3)

Ans (2)
 Question

Essential characteristic of equilibrium is

1 Momentum equals zero

2 Acceleration equals zero

3 K.E. equals zero

4 Velocity equals zero

Ans (2)
 Question

A boy sitting on the topmost berth in the compartment of a train which is just
going to stop on a railway station, drops an apple aiming at the open hand of his
brother sitting vertically below his hands at a distance of about 2 meters.
The apple will fall

1 Precisely on the hand of his brother

2 Slightly away from the hand of his brother in the direction of motion of the
train

3 Slightly away from the hand of his brother in the direction opposite to the
direction of motion of the train

4 None of the above

Ans (2)
 Question

In which of the following cases the net force is not zero?

1 A kite skillfully held stationary in the sky

2 A ball freely falling from a height

3 An aeroplane rising upwards at an angle of 45° with the horizontal with a

constant speed

4 A cork floating on the surface of water

Ans (2)
 Question

A particle is in a straight line motion with uniform velocity. A force is not required

1 To increase the speed

2 To decrease the speed

3 To maintain the same speed

4 To change the direction

Ans (3)
 Question

When a constant force is applied to a body, it moves with uniform

1 Acceleration

2 Velocity

3 Speed

4 Momentum

Ans (1)
 Question

A body of mass 40 g is moving with a constant velocity of 2 cm/s on a horizontal

frictionless table. The force on the body (in dynes) is

1 Zero

2 39200

3 160

4 80

Ans (1)
 Question

There are two bodies A & B of same mass body A is at rest while body B is under
going uniform motion, which is correct statements?

1 Inertia of A > inertia of B

2 Inertia of B > inertia of A

3 Inertia of A = inertia of B

4 Either 1st, 2nd or 3rd depending upon the shape of body.

Ans (3)
 Question

A man is at rest in the middle of a pond on perfectly smooth ice. He can get himself
to the shore by making use of Newton’s

1 First law

2 Second law

3 Third law

4 Law of gravitation

Ans (3)
 Question

If the force of gravity suddenly disappears

1 The mas of all bodies will become zero

2 The weight of all bodies will become zero

3 Both mass and weight of all bodies will become zero

4 Neither mass nor weight of all bodies will become zero

Ans (2)
 Question

When a horse pulls a wagon, the force that causes the horse to move forward is
the force

1 He exerts on the wagon

2 The wagon exerts on him

3 The ground exerts on him

4 He exerts on the ground

Ans (3)
 Question

A particle is acted upon by a force given by (F = 12t + 3t2) N, where t is in seconds.

Find the change in momentum of that particle from t = 1 to t = 3 sec.

1 70

2 55

3 74

4 51

Ans (3)
 Question

For the given momentum time (P-t) graphs find the ratio of force on particles A
and B.

1 √3 : 1

2 1:1

3 1 : √3

4 1:2

Ans (3)
 Question

In which of the following processes no force is needed

1 For uniform acceleration

2 For uniform motion

3 For linear motion

4 To keep the momentum constant

Ans (4)
 Question

Which of the following relations is wrong

𝒅𝒓 𝒅𝟐 𝒓
1 𝑭=𝒎 2 𝑭=𝒎 𝟐
𝒅𝒕 𝒅𝒕

𝒅𝒗 𝒎 𝒗−𝒖
3 𝑭=𝒎 4 𝑭=
𝒅𝒕 𝒕

Ans (1)
 Question

A force of 10 N is applied to a mass of 10gm for 10 seconds. The change of

momentum in mkg/sec units will be

1 10

2 100

3 1000

4 0.01

Ans (2)
 Question

A ball moving with a velocity 20 m/sec has a mass of 50 gm. If collides against a
wall normally and is rebounded normally with the same speed. If the time of
impact of the ball and the wall is 40 mili seconds, the average force exerted on the
wall in dynes is

1 zero

2 1.25 × 107

3 2.5 × 107

4 5 × 106

Ans (4)
 Question

In a circus a horse rider takes a vertically jump on a moving horse, and falls back
on the horse because

1 The inertia of motion is present

2 The length of the circus horse is large

3 The motion is in circular path

4 In reality the rider does not jump

Ans (1)
 Question

A boy holds a hydrogen filled balloon with a string. He is sitting in a train moving
with uniform velocity on a straight track. The string is vertical. On applying
brakes the balloon will

1 in the direction of velocity

2 in the opposite direction of velocity

3 will not move

4 data is insufficient

Ans (1)
 Question

A body is in equilibrium under the action of three forces on it. For this it is
necessary that the three forces

1 Are in or should be in a straight line

2 Should pass through the same point and do not lie in the same plane

3 Should pass through the same point and lie in the same plane

4 Should be mutually perpendicular to each other and pass through a common

point

Ans (3)
 Question

Which statement is wrong in connection with Newton’s second law of motion –

1 It indicates the measure of force

2 It indicates a relation between force and rate of change of velocity

3 It indicates a relation between force and momentum

4 It can furnish the value of inertia

Ans (4)
 Question

Newton’s third law of motion gives

1 Definition of force

2 Magnitude of force

3 Explanation of the creation of force

4 None of these

Ans (3)
 Question

Newton’s second law relates the following quantities

1 Momentum and acceleration

2 Variation in momentum and velocity

3 Variation in momentum and external force

4 Rate of change of force and momentum

Ans (3)
 Question

A parrot is sitting on the floor of a closed glass cage which is in a boy’s hand. If the
parrot starts flying with a constant speed, the boy will feel the weight of the cage
as

1 Unchanged

2 Reduced

3 Increased

4 Nothing can be said

Ans (1)
 Question

A man weighing 100 kg carries a load of 10 kg on his head. He jumps from a tower
with the load on his head. What will be the weight of the load as experienced by
the man?

1 Zero

2 10 kg

3 Slightly more than 10 kg

4 110 kg

Ans (1)
 Question

Force-time graph for the motion of a body is shown in fig. Change in linear
momentum between 0 to 8 s is :-

1 Zero

2 4 N-s

3 8 N-s

4 None

Ans (1)
 Question

When we kick a stone, we get hurt. Due to which of the following properties of
stone does it happens?

1 Inertia

2 Velocity

3 Reaction

4 Momentum

Ans (3)
 Question

A player catches a ball of 200 g moving with a speed of 20 m/s. If the time taken to
complete the catch is 0.5 s, the force exerted on the player's hand is:-

1 8N

2 4N

3 2N

4 0

Ans (1)
 Question

For a body of 50 kg mass, the velocity-time graph is shown in figure. The force
acting on the body is :

1 25 N

2 50 N

3 12.5 N

4 100 N

Ans (2)
 Question

A satellite in force free space sweeps stationary interplanetary dust at a rate

(dM/dt) = + αv. Here v is the velocity. The acceleration of satellite of mass M is:-

1 –2 αv2/M

2 –3 αv2/M

3 – αv2/M

4 – αv2

Ans (3)
 Question

A cricket ball of mass 250 g collides with a bat with velocity 10 m/s and returns
with the same velocity within 0.01 second. The force acted on bat is

1 25 N

2 50 N

3 250 N

4 500 N

Ans (4)
 Question

A body of mass 2 kg is moving with a velocity 8 m/s on a smooth surface. If it is to

be brought to rest in 4 seconds, then the force to be applied is

1 8N

2 4N

3 2N

4 1N

Ans (2)
 Question

If a force of 250 N act on body, the momentum acquired is 125 kg-m/s. What is the
period for which force acts on the body

1 0.5 sec

2 0.2 sec

3 0.4 sec

4 0.25 sec

Ans (1)
 Question

A ball of mass m moves with speed v and it strikes normally with a wall and
reflected back normally, if its time of contact with wall is t then find force exerted
by ball on wall

1 2mv/t

2 mv/t

3 mvt

4 mv/2t

Ans (2)
 Question

A rope of length L is pulled by a constant force F. What is the tension in the rope at
a distance x from the end where the force is applied
𝑭𝑳
1
𝒙
𝑭 𝑳−𝒙
2
𝑳
𝑭𝑳
3
𝑳−𝒙
𝑭𝒙
4
𝑳−𝒙

Ans (2)
 Question

An aircraft is moving with a velocity of 300 ms–1. If all the forces acting on it are
balanced, then

1 It still moves with the same velocity

2 It will be just floating at the same point in space

3 It will fall down instantaneously

4 It will lose its velocity gradually

Ans (1)
 Question

A particle of mass 0.3 kg is subjected to a force F = – kx with k = 15 N/m. What will

be its initial acceleration if it is released from a point 20 cm away from the origin

1 5 m/s2

2 10 m/s2

3 3 m/s2

4 15 m/s2

Ans (2)
 Question

A 0.5 kg ball moving with a speed of 12 m/s strikes a hard wall at an angle of 30°
with the wall. It is reflected with the same speed and at the same angle. If the ball
is in contact with the wall for 0.25 seconds, the average force acting on the wall is

1 48 N

2 24 N

3 12 N

4 96 N

Ans (2)
 Question

In a rocket of mass 1000 kg fuel is consumed at a rate of 40 kg/s. The velocity of

the gases ejected from the rocket is 5 × 104 m/s. The thrust on the rocket is

1 2 × 103 N

2 5 × 104 N

3 2 × 106 N

4 2 × 109 N

Ans (3)
 Question

The force ‘F’ acting on a particle of mass ‘m’ is indicated by the force-time graph
shown below. The change in momentum of the particle over the time interval from
zero to 8 s is

1 24 Ns

2 20 Ns

3 12 Ns

4 6 Ns

Ans (3)
 Question

A bullet is fired from a gun. The force on the bullet is given by F = 600 – 2 × 105 t,
where F is in newtons and t in seconds. The force on the bullet becomes zero as
soon as it leaves the barrel. What is the average impulse imparted to the bullet

1 9 Ns

2 Zero

3 0.9 Ns

4 1.8 Ns

Ans (3)
 Question

A body of mass 0.25 kg is projected with muzzle velocity 100 ms–1 from a tank of
mass 100 kg. What is the recoil velocity of the tank?

1 5 ms–1

2 25 ms–1

3 0.5 ms–1

4 0.25 ms–1

Ans (4)
 Question

A wagon weighing 1000 kg is moving with a velocity 50 km/h on smooth

horizontal rails. A mass of 250 kg is dropped into it. The velocity with which it
moves now is

1 2.5 km/hour

2 20 km/hour

3 40 km/hour

4 50 km/hour

Ans (3)
 Question

A lift is going up. The total mass of the lift and the passenger is 1500 kg.
The variation in the speed of the lift is as given in the graph. The tension in the
rope pulling the lift at t = 11th sec will be

1 17400 N

2 14700 N

3 12000 N

4 Zero

Ans (3)
 Question

A rocket has a mass of 100 kg. It ejects fuel vapours at the rate of 1 kg/sec with a
velocity of 500 m/sec relative to the rocket. It is supposed that the rocket is
outside the gravitational field. The initial upthrust on the rocket when it just
starts moving upwards is

1 Zero

2 500 N

3 1000 N

4 2000 N

Ans (2)
 Question

A block of metal weighing 2 kg is resting on a frictionless plane. It is struck by a jet

releasing water at a rate of 1 kg/s with a speed of 5 m/s. The initial acceleration of
the block will be:

1 2.5 m/s2

2 5 m/s2

3 10 m/s2

4 15 m/s2

Ans (1)
 Question

A ball weighing 10 g hits a hard surface vertically with a speed of 5 m/s and
rebounds with the same speed. The ball remains in contact with the surface for
(0.01) s. The average force exerted by the surface on the ball is:

1 100 N

2 10 N

3 1N

4 0.1 N

Ans (2)
 Question

A water jet, whose cross sectional are is ‘a’ strikes a wall making an angle ‘θ’ with
the normal and rebounds elastically. The velocity of water of density ‘d’ is v.
Force exerted on wall is:

1 2 av2d cos θ

2 2 av2d sin θ

3 2 avd cos θ

4 avd cos θ

Ans (1)
 Question

A player catches a ball of 200 g moving with a speed of 20 m/s. If the time taken to
complete the catch is 0.5 s, the force exerted on the player's hand is:

1 8N

2 4N

3 2N

4 0

Ans (1)
 Question

If force F = 500 – 100t, then impulse as a function of time will be:

1 500t – 50t2

2 50t – 10

3 50 – t2

4 100t2

Ans (1)
 Question

If the force on a rocket moving in force free space with an exhaust velocity of gases
300 m/sec is 210 N, then the rate of combustion of the fuel, is:

1 0.7 kg/s

2 1.4 kg/s

3 2.7 kg/s

4 10.7 kg/s

Ans (1)
 Question

n bullet strike per second elastically on a wall and rebound. What will be the force
exerted on the wall by bullets if mass of each bullet is m:

1 mnv

2 4mnv

3 2mnv

4 mnv/2

Ans (3)
 Question

In the figure given below, the position–time graph of a particle of mass 0·1 kg is
shown. The impulse at t = 2 sec is:

1 0·2 kg-m/s

2 –0·2 kg-m/s

3 0·1 kg-m/s

4 –0·4 kg-m/s

Ans (2)
 Question

A person is standing in an elevator. In which situation he finds his weight less?

1 When the elevator moves upward with constant acceleration

2 When the elevator moves downward with constant acceleration

3 The elevator moves upward with uniform velocity

4 When the elevator moves downward with uniform velocity

Ans (2)
 Question

A 150 g tennis ball coming at a speed of 40 m/s is hit straight back by a bat to
speed of 60 m/s. The magnitude of the average force F on the ball, when it is in
contact for 5 ms with the bat is:

1 2500 N

2 3000 N

3 3500 N

4 4000 N

Ans (2)
 Question

Ten one-rupee coins are put on top of each other on a table. Each coin has a mass
m. Which of the following statements is not true?

1 The force on the 6th coin (counted from the bottom) due to all the coins on
its top is equal to 4mg (downwards).

2 The force on the 6th coin due to the 7th coin is 4mg (downwards)

3 The reaction of the 6th coin on the 7th coin is 4mg (upwards).

4 The total force on the 10th coin is 9mg (downwards)

Ans (4)
 Question

A 140 g ball, in horizontal flight with a speed of 39.0 m/s, is struck by a bat. After
leaving the bat, the ball travels in the opposite direction with speed v2 = 39.0 m/s.
If the impact time Δt for the ball-bat collision is 1.20 ms, what average force acts
on the ball?

1 1308 N

2 1090 N

3 9100 N

4 980 N

Ans (3)
 Question

A disc of mass 1·0 kg is kept floating horizontally in air by firing bullets of mass
0·05 kg each vertically at it, at the rate of 10 per second. If the bullets rebound
with the same speed, the speed with which these are fired will be–

1 0·098 m/s

2 0·98 m/s

3 9·8 m/s

4 98·0 m/s

Ans (3)
 Question

When an object is at rest

1 Force is required to keep it in rest state

2 No force is acting on it

3 A large number of forces may be acting on it which balance each other

4 It is in vacuum

Ans (3)
 Question

A body of mass 2 kg is sliding with a constant velocity of 4 m/s on a frictionless

horizontal table. The force required to keep the body moving with the same
velocity is

1 8N

2 0N

3 2 × 104 N

4 12 N

Ans (2)
 Question

A mass of 10 kg is suspended by a rope of length 2.8 m from a ceiling. A force of 98

N is applied at the midpoint of the rope as shown in figure. The angle which the
rope makes with the vertical in equilibrium is

1 30°

2 60°

3 45°

4 90°

Ans (3)
 Question

Two masses M1 to M2 connected by means of a string which is made to pass over

light, smooth pulley are in equilibrium on a fixed smooth wedge as shown in
figure. If θ = 60° and α = 30°, then the ratio of M1 to M2 is

1 1:2

2 2 : √3

3 1 : √3

4 √3 : 1

Ans (3)
 Question

A body of mass 5 kg is suspended by a spring balance on an inclined plane as

shown in figure. The spring balance measure

1 50 N

2 25 N

3 500 N

4 10 N

Ans (2)
 Question

The tension in the spring is

1 Zero

2 2.5 N

3 5N

4 10 N

Ans (3)
 Question

A mass is suspended by a rope from a rigid support at A as shown in figure.

Another rope is tied at the end B, and it is pulled horizontally with a force F. If the
rope AB makes an angle θ with the vertical in equilibrium, then the tension in the
string AB is

1 F sin θ

2 F/sin θ

3 F cos θ

4 F/cos θ

Ans (2)
 Question

Find the tension T2 for the system shown in figure.

1 1g N

2 2g N

3 5g N

4 6g N

Ans (3)
 Question

A block of mass 4 kg is suspended through two light spring balances A and B in

series. Then A and B will read respectively.

1 4 kg and zero kg

2 zero kg and 4 kg

3 4 kg and 4 kg

4 2 kg and 2 kg

Ans (3)
 Question

When an object is in equilibrium state, then

1 It must be at rest

2 No force is acting on it

3 Its net acceleration must be zero

4 All of these

Ans (3)
 Question

In which of the following graphs, the total change in momentum is zero?

1 2

3 4

Ans (3)
 Question

A weight Mg is suspended from the middle of a rope whose ends are at the same
level. The rope is no longer horizontal. The minimum tension required to
completely straighten the rope is

1 Mg/2

2 Mg cos θ

3 2 Mg cos θ

4 Infinitely large

Ans (4)
 Question

Which of the four arrangements in the figure correctly shows the vector addition
of two forces 𝑭𝟏 and 𝑭𝟐 to yield the third force 𝑭𝟑

1 2

3 4

Ans (1)
 Question

The adjacent figure is the part of a horizontally stretched net. Section AB is

stretched with a force of 10 N. The tensions in the sections BC and BF are

1 10 N, 11 N

2 10 N, 6 N

3 10 N, 10 N

4 Can’t calculate due to insufficient data.

Ans (3)
 Question

A body of mass M at rest explodes into three pieces, two of which of mass M/4 each
are thrown off in perpendicular directions with velocities of 3 m/s and 4 m/s
respectively. The third piece will be thrown off with a velocity of

1 1.5 m/s

2 2.0 m/s

3 2.5 m/s

4 3.0 m/s

Ans (3)
 Question

Two masses m1 and m2 are accelerated uniformly on frictionless surface as

shown. The ratio of the tension T1/T2 :
𝒎𝟏
1
𝒎𝟐
𝒎𝟐
2
𝒎𝟏
𝒎𝟏 + 𝒎𝟐
3
𝒎𝟐
𝒎𝟏
4
𝒎𝟏 + 𝒎𝟐

Ans (4)
 Question

Three blocks of masses m1, m2 and m3 are placed on a horizontal frictionless

surface. A force of 40 N pulls the system. Then calculate the value of T, if m1 = 10
kg, m2 = 6 kg, m3 = 4 kg.

1 40 N

2 20 N

3 10 N

4 5N

Ans (2)
 Question

Blocks are in contact on a frictionless table. A horizontal force F = 3N is applied to

one block as shown. Then force exerted by the smaller block m2 on block m1 is

1 1N

2 2N

3 3N

4 6N

Ans (1)
 Question

A cracker rocket is ejecting gases at a rate of 0.05 kg/s with a velocity 400 m/s.
The accelerating force on the rocket is

1 20 dyne

2 20 N

3 200 N

4 Zero

Ans (2)
 Question

In the figure given below, with what acceleration does the block of mass m will
move? (Pulley and strings are massless and frictionless)

1 g/3

2 2g/5

3 2g/3

4 g/2

Ans (3)
 Question

In the arrangement shown, the mass m will ascend with an acceleration

(Pulley and rope are massless)

1 Zero

2 g/2

3 g

4 2g

Ans (2)
 Question

A rocket of mass 5700 kg ejects mass at a constant rate of 15 kg/s with constant
speed of 12 km/s. The acceleration of the rocket 1 minute after the blast is
(g = 10 m/s2)

1 34.9 m/s2

2 27.5 m/s2

3 3.50 m/s2

4 13.5 m/s2

Ans (2)
 Question

A balloon has 2 g of air. A small hole is pierced into it. The air comes out with a
velocity of 4 m/s. If the balloon shrinks completely in 2.5 s. The average force
acting on the balloon is

1 0.008 N

2 0.0032 N

3 8N

4 3.2 N

Ans (2)
 Question

Two masses as shown are suspended from a massless pulley. Calculate the
acceleration of the 10 kg mass when masses are left free

1 2g/3

2 g/3

3 g/9

4 g/7

Ans (2)
 Question

Two bodies of 5 kg and 4 kg are tied to a string as shown in the figure. If the table
and pulley both are smooth, acceleration of 5 kg body will be equal to

1 g

2 g/4

3 4g/9

4 5g/9

Ans (4)
 Question

A light string passes over a frictionless pulley. To one of its ends a mass of 6 kg is
attached and to its other end a mass of 10 kg is attached. The tension in the string
will be

1 50 N

2 75 N

3 100 N

4 150 N

Ans (2)
 Question

A body of weight 2 kg is suspended as shown in the figure. The tension T1 in the

horizontal string (in kg wt.) is

1 2/√3

2 √3/2

3 2√3

4 2

Ans (3)
 Question

A light string passing over a smooth light pulley connects two blocks of masses m1
and m2 (vertically). If the acceleration of the system is g/8 then the ratio of the
masses is

1 8:1

2 9:7

3 4:3

4 5:3

Ans (2)
 Question

The force-time (F – t) curve of a particle executing linear motion is as shown in the

figure. The momentum acquired by the particle in time interval from zero to
8 second will be
1 –2 N-s

2 +4 N-s

3 6 N-s

4 Zero

Ans (4)
 Question

A 2 kg block is lying on a smooth table which is connected by a body of mass 1 kg

by a string which passes through a pulley. The 1 kg mass is hanging vertically. The
acceleration of block and tension in the string will be

1 3.27 m/s2, 6.54 N

2 4.38 m/s2, 6.54 N

3 3.27 m/s2, 9.86 N

4 4.38 m/s2, 9.86 N

Ans (1)
 Question

In the given diagram, the tension in string C is:

1 100 N

2 70.7 N

3 141 N

4 200 N

Ans (3)
 Question

Find tension in string if θ = 30° and the mass hanged in middle of the string is
equal to 22kg.

1 110 N

2 220 N

3 Infinite

4 Between 110 N & 220 N

Ans (2)
 Question

Two persons hold a rope of negligible weight tightly at its ends so that it is
horizontal. A 15 N weight is attached to the rope at the mid point which now no
longer remains horizontal. The minimum tension required to completely
straighten the top is

1 15 N

2 15/2 N

3 5N

4 Infinitely large

Ans (4)
 Question

A mass of 6 kg is suspended by a rope of length 2 m from a ceiling. A force of 50 N

is applied in horizontal direction at the mid point of the rope. What is the angle
between the rope and the vertical in equilibrium:-
𝟒
1 𝐭𝐚𝐧−𝟏
𝟓
𝟓
2 𝐭𝐚𝐧−𝟏
𝟒
𝟓
3 𝐭𝐚𝐧−𝟏
𝟔

4 None

Ans (3)
 Question

A metal sphere is hung by a string fixed to a wall. The forces acting on the sphere
are shown in fig. Which of the following statements is correct?
(a) 𝑹 + 𝑻 + 𝑾 = 𝟎 (b) T2 = R2 + W2
(c) T = R + W (d) R = W tan θ

1 a, b, c

2 b, c, d

3 a, b, d

4 a, b, c, d

Ans (3)
 Question

The figure shows a horizontal force 𝑭 acting on a block of mass M on an inclined

plane (angle θ). What is the normal reaction on the block?

1 mg sin θ + F cos θ

2 mg sin θ – F cos θ

3 mg cos θ – F sin θ

4 mg cos θ + F sin θ

Ans (4)
 Question

Two blocks A and B of masses 3 m and m respectively are connected by a massless

and inextensible string. The whole system is suspended by a massless spring as
shown in figure. The magnitudes of acceleration of A and B immediately after the
string is cut, are respectively :-

1 g/3, g

2 g, g

3 g/3, g/3

4 g, g/3

Ans (1)
 Question

In following diagram find value of T2.

1 12 N

2 6N

3 4N

4 1N

Ans (1)
 Question

A train has 10 wagons each of mass 1000 kg attached to it. They are being pulled
by force 104 N. Find out force exerted on last four wagons.

1 4 × 103 N

2 4 × 104 N

3 5 × 104 N

4 5 × 103 N

Ans (1)
 Question

𝟏
If m1 = m2 = 1 kg then find out distance travelled by m1 in first sec.
𝟐

1 0.650 m

2 0.625 m

3 0.725 m

4 0.525 m

Ans (2)
 Question

Two masses of 10 kg and 5 kg are suspended from a fixed support as shown in

figure. The system is pulled down with a force of 150 N attached to the lower mass.
The string attached to the support breaks and the system accelerates downwards.
If the downward force continues to act, what is the acceleration of the system?

1 20 m/s2

2 10 m/s2

3 5 m/s2

4 zero

Ans (1)
 Question

A block of mass M is pulled along a horizontal frictionless surface by a rope of

mass m. If a force F is applied at one end of the rope, the force which the rope
exerts on the block is :-

1 F/(M + m)

2 F

3 FM/(m + M)

4 Zero

Ans (3)
 Question

The surface is frictionless, the ratio of T1 and T2 is:-

1 √3 : 1

2 1 : √3

3 1:5

4 5:1

Ans (4)
 Question

Two masses of 10 kg and 20 kg respectively are connected by a massless spring as

shown in the figure. A force of 200 N acts on the 20 kg mass. At the instant shown
the 10 kg mass has an acceleration 4 m/s2 rightwards. What is the acceleration of
20 kg mass?

1 Zero

2 10 m/s2

3 4 m/s2

4 8 m/s2

Ans (4)
 Question

Two blocks each of mass M are resting on a frictionless inclined planes as shown
in figure then

1 The block A moves down the plane

2 The block B moves down the plane

3 Both the blocks remain at rest

4 Both the blocks move down the plane

Ans (1)
 Question

A balloon of mass M is descending with a constant acceleration g/3. When a mass

m is released from the balloon it starts rising with the same acceleration g/3.
The value of m is (Assuming that its volume does not change):-

1 M/2

2 M/4

3 4M

4 2M

Ans (1)
 Question

Gravel is dropped onto a conveyer belt at a rate of 0.5 kg/s. The extra force
required in newton to keep the belt moving at 2 m/s is :-

1 1N

2 2N

3 4N

4 0.5 N

Ans (1)
 Question

A ball of mass m kept at the corner as shown in the figure, is acted by a horizontal
force F. The correct free body diagram of ball is-

1 2

3 4

Ans (2)
 Question

Four blocks of same mass connected by cords are pulled by forces F on a smooth
horizontal surface, as in figure. The tension T1, T2 and T3 will be-

1 T1 = F/4, T2 = 3F/2, T3 = F/4

2 T1 = F/4, T2 = 3F/2, T3 = F/2

3 T1 = 3F/4, T2 = F/2, T3 = F/4

4 T1 = 3F/4, T2 = F/2, T3 = F/2

Ans (3)
 Question

Find acceleration of blocks:-

1 g

2 g/2

3 g/3

4 g/4

Ans (2)
 Question

Two bodies of masses 4 kg and 5 kg are acted upon by the same force. If the
acceleration of lighter body is 2m/sec2, then the acceleration of the heavier body
is:-

1 4.2 m/s2

2 3.6 m/s2

3 2.4 m/s2

4 1.6 m/s2

Ans (4)
 Question

A mass M = 100 kg is suspended with the use of stings A, B and C as shown, W is a

vertical wall and R is a rigid horizontal rod. The tension in string B is:

1 100 g newton

2 zero

3 100√2 gnewton

4 100/√2 gnewton

Ans (1)
 Question

A boy of mass 40 kg is hanging from the horizontal branch of a tree. The tension in
his arms is minimum when the angle between the arms is:-

1 0°

2 90°

3 120°

4 180°

Ans (1)
 Question

The acceleration of the block A is 2 m/s2 down the incline. The ratio of the mass of
A to that of B is-

1 7:6

2 5:2

3 5:3

4 3:4

Ans (2)
 Question

In the arrangement shown, the blocks of unequal masses are held at rest. When
released, acceleration of the blocks is-

1 g/2

2 g

3 a value between zero and g

4 a value that could be greater than g

Ans (3)
 Question

Three masses of 1 kg, 6 kg and 3 kg are connected to each other with threads and
are placed on a table as shown in figure. What is the acceleration with which the
system is moving? (Take g = 10 ms–2):

1 Zero

2 2 ms–2

3 4 ms–2

4 3 ms–2

Ans (2)
 Question

Reading of spring balance is (g 10 m/s2):-

1 1 kg wt

2 2 kg wt

3 3 kg wt

4 4 kg wt

Ans (4)
 Question

The ratio of weight of a man in a stationary lift and in a lift accelerating

downwards with a uniform acceleration is 3 : 2. The acceleration of the lift is:-

1 g/3

2 g/2

3 g

4 4/3 g

Ans (1)
 Question

A block can slide on a smooth inclined plane of inclination θ kept on the floor of a
lift. When the lift is descending with retardation a, the acceleration of the block
relative to the incline is:

1 (g + a) sinθ

2 (g – a)

3 g sin θ

4 (g – a) sinθ

Ans (1)
 Question

The mass of a body measured by a physical balance in a lift at rest is found to be

m. If the lift is going up with an acceleration a, its mass will be measured as:
𝒂
1 m 𝟏−
𝒈

𝒂
2 m 𝟏+
𝒈

3 m

4 zero

Ans (3)
 Question

A pendulum bob is suspended in a Car moving horizontally with acceleration ‘a’

the angle the string will make with vertical is
𝒈
1 𝐭𝐚𝐧–𝟏
𝒂
𝒂
2 𝐭𝐚𝐧 –𝟏
𝒈
𝒂
3 𝐬𝐢𝐧 –𝟏
𝒈
𝒂
4 𝐜𝐨𝐬 –𝟏
𝒈

Ans (2)
 Question

A block of mass m is placed on the floor of lift which is moving with velocity
v = 4t2, where t is time in second and velocity m/s. find the time at which normal
force on the block is three times of its weight.

1 (3g/8)s

2 g/4 s

3 4gs

4 3gs

Ans (2)
 Question

In a lift moving upward with an acceleration of 5 ms–2, a ball of mass 5 kg is placed

on the weight machine. Find the weight of the body in the machine. (g = 10 ms–2)

1 50 N

2 25 N

3 100 N

4 75 N

Ans (4)
 Question

The force exerted by the person on the floor of the elevator is more than the
weight of the person if the elevator is:-
(a) Going up and slowing down
(b) Going up and speeding up
(c) Going down and slowing down
(d) Going down and speeding up

1 a, c

2 b, c

3 a, d

4 b, d
Ans (2)
 Question

In the arrangement shown, the pulleys are fixed and ideal, the string are light,
m1 > m2 and S is a spring balance which is itself massless. The reading of S
(in units of mass) is

1 m1 – m 2
𝟏
2 𝒎𝟏 + 𝒎𝟐
𝟐
𝒎𝟏 𝒎𝟐
3
𝒎𝟏 + 𝒎𝟐
𝟐𝒎𝟏 𝒎𝟐
4
𝒎𝟏 + 𝒎𝟐

Ans (4)
 Question

In the given arrangement, n number of equal masses are connected by strings of

negligible masses. The tension in the string connected to nth mass is
𝒎𝑴𝒈
1
𝒏𝒎 + 𝑴
𝒎𝑴𝒈
2
𝒏𝒎𝑴

3 mg

4 mng

Ans (1)
 Question

For the arrangement shown in the figure, the tension is the string is given by

1 mg/2

2 mg

3 3mg/2

4 2mg

Ans (2)
 Question

A man goes up in a uniformly accelerating lift. He returns downward with the lift
accelerating at the same rate. The ratio of apparent weights in the two cases is
2 : 1. The acceleration of the lift is

1 g/3

2 g/4

3 g/5

4 g/6

Ans (1)
 Question

A man is at rest in the middle of a pond on perfectly smooth ice. He can get himself
to the shore by making use of Newton’s

1 First law

2 Second law

3 Third law

4 All the laws

Ans (3)
 Question

If pulleys shown in the diagram are smooth and massless and a1 and a2 are
acceleration of blocks of mass 4 kg and 8 kg respectively, then

1 a1 = a2

2 a1 = 2a2

3 2 a1 = a2

4 a1 = 4a2

Ans (2)
 Question

What is the acceleration of 3 kg mass when acceleration of 2 kg mass is 2 m/s2 as

shown?

1 3 m/s2

2 2 m/s2

3 0.5 m/s2

4 Zero

Ans (2)
 Question

A dynamometer D is attached to two blocks of masses 6 kg and 4 kg as shown in

the figure. The reading of the dynamometer is

1 18 N

2 28 N

3 38 N

4 48 N

Ans (3)
 Question

A small metallic sphere of mass m is suspended from the ceiling of a car

accelerating on a horizontal road with constant acceleration a. The tension in the
string attached with metallic sphere is

1 mg

2 m(g + a)

3 m(g – a)

4 𝒎 𝒈𝟐 + 𝒂𝟐

Ans (4)
 Question

In the figure, what should be mass m so that block A slides up with a constant
velocity?

1 2 kg

2 1 kg

3 3 kg

4 4 kg

Ans (2)
 Question

A block is placed on a rough horizontal plane. Three horizontal forces are applied
on the block as shown in the figure. If the block is in equilibrium, find the friction
force acting on the block.

1 𝟓𝟎𝒊Ƹ − 𝟐𝟎𝒋Ƹ

2 𝟏𝟓𝟎𝒊Ƹ − 𝟐𝟎𝟎𝒋Ƹ

3 𝟏𝟎𝟎𝒊Ƹ − 𝟐𝟎𝟎𝒋Ƹ

4 𝟏𝟎𝟎𝒊Ƹ − 𝟐𝟎𝒋Ƹ

Ans (3)
 Question

A block of mass m lies on wedge of mass M as shown in figure. With what

minimum acceleration must the wedge be moved towards right horizontally so
that block m falls freely.

1 a = g tanθ

2 a = g cotθ

3 a = g sinθ

4 a = g cosθ

Ans (2)
 Question

In the system shown, the blocks A, B and C are of weight 4W, W and W respectively.
The system set free. The tension in the string connecting the blocks B and C is

1 2W/3

2 6W/5

3 5W/3

4 4W/3

Ans (4)
 Question

A force of 100 N is applied on a block of mass 3 kg as shown in figure. The

𝟏
coefficient of friction between the wall and the surface of the block is . Calculate
𝟒
frictional force acting on the block.

1 20 N

2 10 N

3 15 N

4 30 N

Ans (1)
 Question

In arrangement shown the block A of mass 15 kg is supported in equilibrium by

the block B. Mass of the block B is closest to

1 2 kg

2 3 kg

3 4 kg

4 5 kg

Ans (2)
 Question

Two blocks of masses 2.0 kg and 3.0 kg are connected by light inextensible string.
The string passes over an ideal pulley pivoted to a fixed axel on a smooth incline
plane as shown in the figure. When the blocks are released, find magnitude of
their accelerations.

1 2 m/s2

2 3 m/s2

3 1 m/s2

4 4 m/s2

Ans (3)
 Question

Force F is applied on upper pulley. If F = 30t N where t is time in second. Find the
time when m1 loses contact with floor.

1 t = 1 sec.

2 t = 2 sec.

3 t = 0.5 sec.

4 t = 1.5 sec.

Ans (2)
 Question

In the given figure, find mass of the block A, if it remains at rest, when the system
is released from rest. Pulleys and strings are massless. [g = 10 m/s2]

1 m

2 2m

3 2.5 m

4 3m

Ans (4)
 Question

In the system shown, the blocks A, B and C are of weight 4 W, W and W

respectively. The system set free. The tension in the string connecting the blocks B
and C is

1 2W/3

2 W

3 4W/3

4 5W/3

Ans (3)
 Question

Block A is moving away from the wall at a speed v and acceleration a.

1 Velocity of B is v with respect to A.

2 Acceleration of B is a with respect to A.

3 Acceleration of B is 4a with respect to A.

4 Acceleration of B is √17a with respect to A.

Ans (4)
 Question

In the arrangement shown in figure the ends P and Q of an unstretch able string
move downwards with uniform speed U. Pulleys A and B are fixed. Mass M moves
upwards with a speed

1 2U cos θ

2 U cos θ

3 2U/cosθ

4 U/cosθ

Ans (4)
 Question

The pulleys and strings shown in the figure are smooth and of negligible mass.
For the system to remain in equilibrium, the angle θ should be

1 0°

2 30°

3 45°

4 60°

Ans (3)
 Question

A string of negligible mass going over a clamped pulley of mass m supports a block
of mass M as shown in the figure. The force on the pulley by the clamp is given by

1 𝟐𝑴𝒈

2 𝟐𝒎𝒈

3 𝑴+𝒎 𝟐 + 𝒎𝟐 𝒈

4 𝟐
𝑴+𝒎 + 𝑴𝟐 𝒈

Ans (4)
 Question

A man slides down a light rope whose breaking strength is η times the weight of
man (η < 1). The maximum acceleration of the man so that the rope just breaks is

1 g (1 – η)

2 g (1 + η)

3 gη

4 g/η

Ans (1)
 Question

In the arrangement as shown, tension T2 is (g = 10 m/s2)

1 50 N

2 100 N

3 50√3N

4 100√3N

Ans (2)
 Question

In the figure shown, find out the value of θ [assume string to be tight]

𝟑
1 𝐭𝐚𝐧 −𝟏
𝟒

𝟒
2 𝐭𝐚𝐧−𝟏
𝟑
𝟑
3 𝐭𝐚𝐧 −𝟏
𝟖

4 None of these

Ans (1)
 Question

Mr. A. B and C are trying to put a heavy piston into a cylinder at a mechanical
workshop in railway yard. If they apply forces F1. F2 and F3 respectively on ropes
then for which set of forces at that instant, they will be able to perform the said
job?

1 𝟑𝑭𝟏 = 𝑭𝟐 + 𝟐𝑭𝟑

2 2F1 = F2 + F3

𝑭𝟑
3 𝟐𝑭𝟐 = 𝟑𝑭𝟏 −
𝟐

4 𝑭𝟑 = 𝟐𝑭𝟏 − 𝟑𝑭𝟐
Ans (1)
 Question

What is the minimum value of F needed so that block begins to move upward on
frictionless incline plane as shown

𝛉
1 𝐌𝐠 𝐭𝐚𝐧
𝟐
𝛉
2 𝐌𝐠 𝐜𝐨𝐭
𝟐
𝐌𝐠 𝐬𝐢𝐧 𝛉
3
𝟏 + 𝐬𝐢𝐧 𝛉
𝛉
4 𝐌𝐠 𝐬𝐢𝐧
𝟐

Ans (1)
 Question

Two blocks of mass M and m are kept on the trolley whose all surfaces are smooth
select the correct statement

1 If F = 0 blocks cannot remain stationary

2 For one unique value of F, blocks will be stationary

3 Blocks cannot be stationary for any value of F because all surfaces are smooth

4 Both (1) & (2)

Ans (4)
 Question

Which of the following is self-adjusting force?

1 Static friction

2 Limiting friction

3 Kinetic friction

4 Rolling friction

Ans (1)
 Question

Maximum force of friction is called

1 Limiting friction

2 Static friction

3 Sliding friction

4 Rolling friction

Ans (1)
 Question

The limiting friction between two bodies in contact is independent of

1 Nature of the surface in contact

2 The area of surfaces in contact

3 Normal reaction between the surfaces

4 The materials of the bodies

Ans (2)
 Question

In the figure shown, horizontal force F1 is applied on a block but the block does
not slide. Then as the magnitude of vertical force F2 is increased from zero the
block begins to slide; the correct statement is

1 The magnitude of normal reaction on block increases

2 Static frictional force acting on the block increases

3 Maximum value of static frictional force decreases

4 All of these

Ans (3)
 Question

A block of mass 2 kg is kept on the floor. The coefficient of static friction is 0.4. If a
force F of 2.5 Newton’s is applied on the block as shown in the figure, the frictional
force between the block and the floor will be:

1 2.5 N

2 5N

3 7.84 N

4 10 N

Ans (1)
 Question

A body of mass 2 kg is kept by pressing to a vertical wall by a force of 100 N. The

coefficient of friction between wall and body is 0.3. Then the frictional force is
equal to:

1 6N

2 20 N

3 600 N

4 700 N

Ans (2)
 Question

A car is moving along a straight horizontal road with a speed v0. If the coefficient
of friction between the tyres and the road is μ then the shortest distance in which
the car can be stopped is______. (Coefficient of friction is μ)
𝒗𝟐𝟎
1
𝟐𝛍𝒈
𝒗𝟎
2
𝛍𝒈
𝟐
𝒗𝟎
3
𝛍𝒈
𝒗𝟎
4
𝛍

Ans (1)
 Question

A block B is pushed momentarily along a horizontal surface with an initial velocity

v, if μ is the coefficient of sliding friction between B and the surface, block B will
come to rest after a time:

1 v/gμ

2 gμ/v

3 g/v

4 v/g

Ans (1)
 Question

Two blocks of masses m1 and m2 connected by a string are placed gently over a
fixed inclined plane, such that the tension in the connecting string is initially, zero.
The coefficient of friction between m1 and inclined plane is μ1; between m2 and
the inclined plane is μ2. The tension in the string shall continue to remain zero if

1 μ1 > tanα and μ2 < tanβ

2 μ1 < tanα and μ2 > tanβ

3 μ1 > tanα and μ2 > tanβ

4 μ1 < tanα and μ2 < tanβ

Ans (3)
 Question

Figure shows a block kept on a rough inclined plane. The maximum external force
down the incline for which the block remains at rest 1 N while the maximum
external force up the incline for which the block is at rest is 7 N. The coefficient of
static friction μ is:

1 √3/2

2 1/√6

3 √3

4 4/(3√3)

Ans (4)
 Question

Two persons pull each other through a massless rope in 'tug of war' game.
Who will win?

1 One whose weight is more

2 One who pulls the rope with a greater force

3 One who applies more friction force (shear force) on ground

4 One who applies more normal force (compressive force) on ground

Ans (3)
 Question

A block of mass 4 kg is kept on ground. The coefficient of friction between the

block and the ground is 0.80. An external force of magnitude 30 N is applied
parallel to the ground. The resultant force exerted by the ground on the block is:

1 40 N

2 30 N

3 0N

4 50 N

Ans (4)
 Question

A block weights W is held against a vertical wall by applying a horizontal force F.

The minimum value of F needed to hold the block is

1 Less than W

2 Equal to W

3 Greater than W

4 Data is insufficient

Ans (3)
 Question

In the figure shown calculate the angle of friction. The block does not slide.
Take g = 10 m/s2.
𝟏
1 tanθ =
𝟐

𝟏
2 tanθ =
𝟑

𝟏
3 tanθ =
𝟐

4 tanθ = 𝟑

Ans (1)
 Question

A rough vertical board has an acceleration ‘a’ so that a 2 kg block pressing against
it does not fall. The coefficient of friction between the block and the board should
be

1 > g/a

2 <g/a

3 =g/a

4 >a/g

Ans (1)
 Question

The coefficient of static friction between two surfaces depend on

1 The nature of surface

2 The shape of the surface in contact

3 The area of contact

4 All of the above

Ans (1)
 Question

A block of mass 2 kg is placed on the floor. The coefficient of static friction is

0.4. Force of 2.8 N is applied on the block. The force of friction between the block
and the floor is

1 2.8 N

2 8.0 N

3 2.0 N

4 zero

Ans (1)
 Question

A body of mass m moves with a velocity v on a surface whose friction coefficient is

μ. If the body covers a distance s and finally comes to rest then v will be:

1 𝟐𝛍𝒈𝒔

2 𝛍𝒈𝒔

3 𝛍𝒈𝒔/𝟐

4 𝟑𝛍𝒈𝒔

Ans (1)
 Question

A box ‘A’ is lying on the horizontal floor of the compartment of a train running
along horizontal rails from left to right. At time ‘t’, it decelerates. Then the reaction
R by the floor on the box is given best by

1 2

3 4

Ans (3)
 Question

A wooden block of mass m resting on a rough horizontal table (coefficient of

friction = μ) is pulled by a force F as shown in figure. The acceleration of the block
moving horizontally is:
𝑭cosθ
1
𝒎

𝛍𝑭sinθ
2
𝑴

𝑭
3 (cos θ + μ sin θ) – μg
𝒎

4 None

Ans (3)
 Question

The frictional force of the air on a body of mass 0.25 kg, falling with an
acceleration of 9.2 m/s2, will be:

1 1.0 N

2 0.55 N

3 0.25 N

4 0.15 N

Ans (4)
 Question

A block of mass 15 kg is placed on a long trolley. The coefficient of friction

between the block and trolley is 0.18. The trolley accelerates from rest with
0.5 m/s2 for 20 s. then what is the friction force?

1 3.5 N

2 133.3 N

3 7.5 N

4 N.O.T

Ans (3)
 Question

A block of mass 0.1 kg. is pressed against a wall with a horizontal force of 5N as
shown in the figure. If the coefficient of friction between the wall and the block is
0.5 then the frictional force acting on the block will be (g = 9.8 m/s2):-

1 9.8 N

2 2.5 N

3 0.98 N

4 0.49 N

Ans (3)
 Question

A horizontal force of 10 N is necessary to just hold a block stationary against a

wall. The coefficient of friction between the block and wall is 0.2. The weight of
the block is :-

1 20 N

2 50 N

3 100 N

4 2N

Ans (4)
 Question

Maximum value of static friction is called

1 Limiting friction

2 Rolling friction

3 Normal reaction

4 Coefficient of friction

Ans (1)
 Question

Which of the following statements is not true

1 The coefficient of friction between two surfaces increases as the surface in

contact are made rough

2 The force of friction acts in a direction opposite to the applied force

3 Rolling friction is greater than sliding friction

4 The coefficient of friction between wood and wood is less than 1

Ans (3)
 Question

A body is placed on an inclined plane and has to be pushed down in order to make
it move. The angle made by the normal reaction with the vertical will be:-

1 Equal to angle of repose

2 Equal to the angle of friction

3 Less than the angle of repose

4 More than the angle of friction

Ans (3)
 Question

A block slides with constant velocity on a plane inclined at an angle θ. The same
block is pushed up the plane with an initial velocity v0. The distance covered by
the block before coming to rest is :-
𝒗𝟐𝟎
1
𝟐𝒈 𝐬𝐢𝐧 𝛉
𝒗𝟐𝟎
2
𝟒𝒈 𝐬𝐢𝐧 𝛉
𝒗𝟐𝟎 𝐬𝐢𝐧𝟐 𝛉
3
𝟐𝒈
𝒗𝟐𝟎 𝐬𝐢𝐧𝟐 𝛉
4
𝟒𝒈

Ans (2)
 Question

A block of mass m is lying on an inclined plane. The coefficient of friction between

the plane and the block is µ. The force (F1) required to move the block up the
inclined plane will be:

1 mg sin θ + µ mg cos θ

2 mg cos θ – µ mg sin θ

3 mg sin θ – µ mg cos θ

4 mg cos θ + µ mg sin θ

Ans (1)
 Question

A body is sliding down an inclined plane (angle of inclination 45°). If the

coefficient of friction is 0.5 and g = 9.8 m/s2, then the downward acceleration of
the body in m/s2 is:

1 4.9/√2

2 4.9√2

3 19.6√2

4 4.9

Ans (1)
 Question

A block has been placed on an inclined plane with the slope angle θ, the block
slides down the plane at constant speed. The coefficient of kinetic friction is equal
to:-

1 sin θ

2 cos θ

3 g

4 tan θ

Ans (4)
 Question

A block of mass m lying on a rough horizontal plane is acted upon by a horizontal

force P and another force Q inclined at an angle θ to the vertical. The block will
remain in equilibrium if the coefficient of friction between it and the surface is :-

𝑷 + 𝑸 𝐬𝐢𝐧 𝛉 𝑷 𝐜𝐨𝐬 𝛉 + 𝑸
1 2
𝒎𝒈 + 𝑸 𝐜𝐨𝐬 𝛉 𝒎𝒈 − 𝑸 𝐬𝐢𝐧 𝛉

𝑷 + 𝑸 𝐜𝐨𝐬 𝛉 𝑷 𝐬𝐢𝐧 𝛉 + 𝑸
3 4
𝒎𝒈 + 𝑸 𝐬𝐢𝐧 𝛉 𝒎𝒈 − 𝑸 𝐜𝐨𝐬 𝛉

Ans (1)
 Question

A block of mass 5 kg resting on a horizontal surface is connected by a cord,

passing over a light frictionless pulley to a hanging block of mass 5 kg.
The coefficient of kinetic friction between the block and the surface is 0.5. Tension
in the cord is (g = 9.8 m/s2)

1 49 N

2 Zero

3 36.75 N

4 12.75 N

Ans (3)
 Question

The coefficient of static friction, μs, between block A of mass 2 kg and the table as
shown in the figure is 0.2. What would be the maximum mass value of block B so
that the two blocks do not move? The string and the pulley are assumed to be
smooth and massless. (g = 10 m/s2)

1 4.0 kg

2 0.2 kg

3 0.4 kg

4 2.0 kg

Ans (3)
 Question

A body is placed on a rough inclined plane of inclination θ. As the angle θ is

increased from 0° to 90° the contact force between the block and the plane

1 Remains constant

2 Decreases

3 First decreases then increases

4 First increases then decreases

Ans (2)
 Question

A block of mass 2 kg rests on a rough inclined plane making an angle of 30° with
the horizontal. The coefficient of static friction between the block and the plane is
0.7. The frictional force on the block is–

1 0.7 × 9.8 Newton

2 9.8 Newton

3 0.7 × 9.8 𝟑 Newton

4 9.8 × 𝟑 Newton

Ans (2)
 Question

A boat or an aeroplane has a pointed or tapering front/head. Why?

1 To increase the friction of fluid

2 To reduce the friction of fluid

3 To look good

4 For no reason

Ans (2)
 Question

The frictional force exerted by fluids is also called___________.

1 drug

2 drag

3 drop

4 drown

Ans (2)
 Question

Four children were asked to arrange forces due to rolling, static and sliding
frictions in a increasing order. Their arrangements are given below. Choose the
correct arrangement.

1 Rolling, Static, Sliding

2 Static, Rolling, Sliding

3 Rolling, sliding, static

4 Sliding, Static, Rolling

Ans (3)
 Question

Lubricants are substance which

1 Increases friction

2 Are used to light fire

3 Reduces friction

4 Are used to put off fire

Ans (3)
 Question

A matchstick struck on a matchbox catches fire easily because

1 Friction may cause fire

2 of chemical reaction

3 Force heated the match stick

4 None of the above

Ans (2)
 Question

Tyres are treaded to

1 To look good

2 Increase friction

3 To increase its longevity

4 To increase weight of the tyre

Ans (2)
 Question

When two surface are coated with a lubricant, then they

1 Stick to each other

2 Slide upon each other

3 Roll upon each other

4 None of these

Ans (2)
 Question

Which one of the following statements is incorrect?

1 Rolling friction is smaller than sliding friction.

2 Limiting value of static friction is directly proportional to normal reaction.

3 Frictional force opposes the relative motion.

4 Coefficient of sliding friction has dimensions of length.

Ans (4)
 Question

It is easier to draw up a wooden block along an inclined plane than to haul it

vertically, principally because

1 The friction is reduced

2 The mass becomes smaller

3 Only a part of the weight has to be overcome

4 ‘g’ becomes smaller

Ans (3)
 Question

Rolling friction is smaller than?

1 Sliding friction

2 Static friction

3 Fluid friction

4 All of the above

Ans (4)
 Question

A 20 kg block is resting on a horizontal floor. A force of 75 N is required to just

move the block and a force of 60 N is required to move the block with constant
velocity then coefficient of static friction is:

1 0.375

2 0.44

3 0.52

4 0.60

Ans (1)
 Question

The graph between applied force and frictional force for a body of mass 50 kg
placed in a horizontal surface is as shown in figure the value of coefficient of static
and kinetic friction will be:

1 0.4, 0.3

2 0.3, 0.2

3 0.4, 0.2

4 0.2, 0.3

Ans (1)
 Question

A 2 kg block is resting on horizontal surface. If coefficient of static friction is

0.4 and 2.5 N force is applied on the block then the friction on the block is:-

1 2.5 N

2 5N

3 7. 84 N

4 10 N

Ans (1)
 Question

A block is mass ‘m’ is resting on the floor of a lift which is moving downward with
acceleration of ‘g’. If the block is pulled along the surface and coefficient of friction
is μ then the friction on block is:-

1 mg

2 μmg

3 2 μmg

4 zero

Ans (4)
 Question

A marble block of mass 2 kg lying on ice when given a velocity of 6m/s is stopped
by friction in 10s. Then the coefficient of friction is-

1 0.02

2 0.03

3 0.06

4 0.01

Ans (3)
 Question

A rope lies on a table such that a part of it hangs down the table, when the length
of hanging part is 1/3 of entire length the rope just begins to slide. The coefficient
of friction between the rope and the table is:-

1 2/3

2 1/2

3 1/3

4 1/6

Ans (2)
 Question

The static friction is-

1 Equal to dynamic friction

2 Always less than dynamic friction

3 Always greater than dynamic friction

4 Sometime greater and sometime equal to dynamic friction

Ans (4)
 Question

A block of mass 2kg rests on a rough inclined plane making an angle of 30° with
the horizontal. The coefficient of static friction between the block and the plane is
0.7. The frictional force on the block is-

1 0.7 × 9.8 Newton

2 9.8 Newton

3 0.7 × 9.8√3 Newton

4 9.8 × √3 Newton

Ans (2)
 Question

A force F is applied on a block of mass m on horizontal surface. The coefficient of

friction between the contact surface is μ. The acceleration of m will be –

1 (F-μmg)/m

2 Zero

3 May be (1) or (2)

4 None of these

Ans (3)
 Question

A conveyor belt is moving horizontally with a uniform velocity of 2 m/sec.

Material is dropped at one end at the rate of 5 kg/sec and discharge at the other
end. Neglecting the friction, the force required to move the belt is (N)-

1 10

2 15

3 20

4 40

Ans (1)
 Question

A cork and a metal bob are connected by a string as shown in figure. If the beaker
is given an acceleration towards left then the cork will be thrown towards-

1 Right

2 Left

3 Upwards

4 Downwards

Ans (2)
 Question

The elevator shown in figure is descending, with an acceleration of 2 m/s2.

The mass of the block A is 0.5 kg. The force exerted by the block A on the block B is

1 2N

2 4N

3 6N

4 8N

Ans (2)
 Question

In the figure mass M = 10 gm, is placed on an inclined plane. In order to keep it at

rest, the value of mass ‘m’ will be –

1 5 gm

2 𝟏𝟎 𝟑𝒈𝒎

3 0.10 gm

4 𝟑𝒈𝒎

Ans (1)
 Question

A block is placed on a table. The force of reaction will be-

1 Downwards by the table

2 Upwards by the table

3 No reaction force

4 None of these

Ans (2)
 Question

A fireman of mass 60 kg slides down a pole. He is pressing the pole with a force of
600 N. The coefficient of friction between the hands and the pole is 0.5, with what
acceleration will the fireman slide down (g = 10 m/s2)

1 1 m/s2

2 2.5 m/s2

3 10 m/s2

4 5 m/s2

Ans (4)
 Question

𝟏
A heavy body of mass 25 kg is to be dragged along a horizontal plane 𝛍 = .
𝟑
The least force required is

1 25 kgf

2 2.5 kgf

3 12.5 kgf

4 6.25 kgf

Ans (3)
 Question

If the coefficient of friction between A and B is μ, the maximum horizontal

acceleration of the wedge A for which B will remain at rest w.r.t. the wedge is:

1 μg

2 g((1+μ)/(1-μ))

3 g/μ

4 g((1-μ)/(1+μ))

Ans (2)
 Question

A 60 kg body is pushed with just enough force to start it moving across a floor and
the same force continues to act afterwards. The coefficient of static friction and
sliding friction are 0.5 and 0.4 respectively. The acceleration of the body is.

1 6 m/s2

2 4.9 m/s2

3 3.92 m/s2

4 1 m/s2

Ans (4)
 Question

A force of 750 N is applied to a block of mass 102 kg to prevent it from sliding on a

plane with an inclination angle 30° with the horizontal. If the coefficient of static
friction and kinetic friction between the block and the plane are 0.4 and 0.3 then
the frictional force acting on the block is:
1 750 N

2 500 N

3 345 N

4 250 N

Ans (1)
 Question

The force required to just move a body up an inclined plane is double the force
required to just prevent the body from sliding down the plane. The coefficient of
friction is µ. The inclination θ of the plane is :-

1 tan–1 (µ)

2 tan–1 (µ/2)

3 tan–1 (2µ)

4 tan–1 (3µ)

Ans (4)
 Question

A body of mass 100 g is sliding on a inclined plane with an inclination of 60°. What
is the frictional force experienced, if coefficient of friction is 1.7?
(Take g = 10 m/s2)

1 0.85 N

2 0.95 N

3 1.05 N

4 1.145 N

Ans (4)
 Question

On the horizontal surface of a truck a block of mass 1 kg is placed (µ = 0.6) and

truck is moving with acceleration 5 m/sec2 then the frictional force on the block
will be

1 5N

2 6N

3 5.88 N

4 8N

Ans (1)
 Question

Starting from rest, a body slides down a 45° inclined plane in twice the time it
takes to slide down the same distance in the absence of friction. The coefficient of
friction between the body and the inclined plane is

1 0.80

2 0.75

3 0.25

4 0.33

Ans (1)
 Question

The upper half of an inclined plane of inclination θ is perfectly smooth while the
lower half rough. A block starting from rest at the top of the plane will again come
to rest at the bottom if the coefficient of friction between the block and the lower
half of the plane is given by.

1 µ = 2 tan θ

2 µ = tan θ

3 µ = 2/(tan θ)

4 µ = 1/tan θ

Ans (2)
 Question

Two blocks of masses 2 kg and 3 kg placed on a horizontal surface are connected

by a massless string. If 3 kg is pulled by 10 N as shown in figure, then force of
friction acting on 2 kg is [Take g = 10 m/s2]

1 6N

2 4N

3 8N

4 12 N

Ans (1)
 Question

In the given figure, F = 200 N, m1 = 20 kg, m2 = 25 kg, g = 10 m/s2. Find the friction
acting on the block of mass m2 [Take g = 10 m/s2]

1 125 N

2 120.5 N

3 100 N

4 123.2 N

Ans (2)
 Question

A 2 kg block (1) is placed on 8 kg block (2) which rests on a table. Coefficient of

friction between (1) and (2) is 0.2 and between (2) and table is 0.5. A 25 N
horizontal force is applied on the block (2), then the friction force between the
blocks (1) and (2) is :-

1 Zero

2 3.9 N

3 5N

4 49 N

Ans (3)
 Question

Two blocks (A) 2 kg and (B) 5 kg rest one over the other on a smooth horizontal
plane. The coefficient of static and dynamic friction between (A) and (B) is the
same and equal to 0.60. The maximum horizontal force F that can be applied to
(B) in order that both (A) and (B) do not have any relative motion is :

1 42 N

2 42 kgf

3 5.4 kgf

4 1.2 N

Ans (1)
 Question

In the arrangement coefficient of friction between the two blocks is µ = 1/2. The
force of friction acting between the two blocks is:

1 8N

2 6N

3 10 N

4 12 N

Ans (1)
 Question

Calculate the acceleration of the block and trolly system shown in the figure.
The coefficient of kinetic friction between the trolly and the surface is 0.05.
(g = 10 m/s2, mass of the string is negligible and no other friction exists).

1 1.25 m/s2

2 1. 50 m/s2

3 1.66 m/s2

4 1. 00 m/s2

Ans (1)
 Question

Determine the maximum acceleration of the train in which a box lying on its floor
will remain stationary, given that the coefficient of static friction between the box
and the train’s floor is 0.15.

1 0 m/s2

2 0.5 m/s2

3 2.5 m/s2

4 1.5 m/s2

Ans (4)
 Question

A body takes time t to reach the bottom of an inclined plane of angle θ with the
horizontal. If the plane is made rough, time taken now is 2t. The coefficient of
friction of the surface is

1 3/4 tanθ

2 2/3 tanθ

3 1/4 tanθ

4 1/2 tanθ

Ans (1)
 Question

A block is kept on an inclined plane of inclination θ of length l. The velocity of

particle at the bottom of inclined is (the coefficient of friction is μ)

1 𝟐𝒈𝒍(𝛍𝐜𝐨𝐬𝛉 − 𝐬𝐢𝐧 𝛉)

2 𝟐𝒈𝒍(𝐬𝐢𝐧𝛉 − 𝛍 𝐜𝐨𝐬 𝛉)

3 𝟐𝒈𝒍(𝐬𝐢𝐧𝛉 + 𝛍 𝐜𝐨𝐬 𝛉)

4 𝟐𝒈𝒍(𝐜𝐨𝐬𝛉 + 𝛍 𝐬𝐢𝐧 𝛉)

Ans (2)
 Question

Consider a car moving on a straight road with a speed of 100 m/s. The distance at
which car can be stopped is [μk = 0.5]

1 100 m

2 400 m

3 800 m

4 1000 m

Ans (4)
 Question

If mass of A = 10 kg, coefficient of static friction = 0.2, coefficient of kinetic friction

= 0.2. Then mass of B to start motion is

1 2 kg

2 2.2 kg

3 4.8 kg

4 200 kg

Ans (1)
 Question

A vehicle of mass m is moving on a rough horizontal road with momentum p. If the

coefficient of friction between the tyres and the road is μ, then the stopping
distance is
𝒑
1
𝟐𝛍𝒎𝒈
𝒑𝟐
2
𝟐𝛍𝒎𝒈
𝒑
3
𝟐𝛍𝒎𝟐 𝒈
𝒑𝟐
4
𝟐𝛍𝒎𝟐 𝒈

Ans (4)
 Question

A boy of mass 50 kg produces an acceleration of 2m/s2 in a block of mass 20 kg by

pushing it in horizontal direction. The body moves with the block such that boy
and the block have same acceleration. There is no friction between the block and
fixed horizontal surface but there is friction between foot of the boy and
horizontal surface. Find friction force (in Newton) exerted by the horizontal
surface on the boy.

1 120

2 140

3 160

4 200
Ans (2)
 Question

A force F = t is applied to a block A as shown in figure, where t is time in seconds.

The force is applied at t = 0seconds when the system was at rest. Which of the
following graph correctly gives the frictional force between A and horizontal
surface as a function of time t. [Assume that at t = 0, tension in the string
connecting the two blocks is zero].

1 2

3 4

Ans (3)
 Question

With reference to the figure shown, if the coefficient of friction at the surfaces is
0.42, then the force required to pull out the 6.0 kg block with an acceleration of
1.50m/s2 will be:

1 36 N

2 24 N

3 84 N

4 51 N

Ans (4)
 Question

The coefficient of friction between 4 kg and 5 kg blocks 0.2 and between 5 kg

block and ground is 0.1 respectively. Choose the correct statements.

1 Minimum force needed to cause system to move is 1 N

2 When force is 4 N static friction at all surfaces is 4 N to keep system at rest

3 Maximum acceleration of 4 kg block is 2 m/s2

4 Slipping between 4 kg and 5 kg blocks start when F is 17 N

Ans (3)
 Question

A block A with mass 100 kg is resting on another block B of mass 200 kg. As shown
in figure a horizontal rope tied to a wall holds it. The coefficient of friction
between A and B is 0.2 while coefficient of friction between B and the ground is
0.3. The minimum required force F to start moving B will be:

1 900 N

2 100 N

3 1100 N

4 1200 N

Ans (3)
 Question

A body B lies on a smooth horizontal table and another body A is placed on B.

The coefficient of friction between A and B is μ. What acceleration given to B will
cause slipping to occur between A and B

1 μg

2 g/μ

3 μ/g

4 √μg

Ans (1)
 Question

A 40 kg slab rests on a frictionless floor as shown in the figure. A 10 kg block rests

on the top of the slab. The static coefficient of friction between the block and slab
is 0.60 while the kinetic friction is 0.40. The 10 kg block is acted upon by a
horizontal force 100 N. If g = 9.8 m/s2, the resulting acceleration of the slab
will be :

1 1 m/s2

2 1.5 m/s2

3 2 m/s2

4 6 m/s2
Ans (1)
 Question

In the figure 𝒎𝑨 = 𝒎𝑩 = 𝒎𝑫 = 𝟔𝟎kg. The coefficient of friction between D and

ground is 0.5, B and ground is 0.3, A an B is 0.4. D is pulling the string with the
maximum possible force without moving. Then tension in the string connected to
A will be :

1 120 N

2 60 N

3 100 N

4 zero

Ans (4)
 Question

In the system shown in figure the friction coefficient between ground and bigger
block is μ. There is no friction between both the blocks. The string connecting
both the block is light; all three pulleys are light and frictionless. Then the
minimum limiting value of μ so that the system remains in equilibrium is:

1 1/2

2 1/3

3 2/3

4 3/2

Ans (3)
 Question

The system is pushed by a force F as shown in figure. All surfaces are smooth
except between B and C. Friction coefficient between B and C is μ. Minimum value
of F to prevent block B from downward slipping is :

𝟑
1 𝒎𝒈
𝟐𝛍
𝟓
2 𝒎𝒈
𝟐𝛍
𝟓
3 𝛍𝒎𝒈
𝟐
𝟑
4 𝛍𝒎𝒈
𝟐
Ans (2)
 Question

Two bodies of mass 3 kg and 4 kg are suspended at the ends of massless string
passing over a frictionless pulley. The acceleration of the system is (g = 9.8 m/s2)

1 4.9 m/s2

2 2.45 m/s2

3 1.4 m/s2

4 9.5 m/s2

Ans (3)
 Question

Three solids of masses m1, m2 and m3 are connected with weightless string in
succession and are placed on a frictionless table. If the mass m3 is dragged with a
force T, the tension in the string between m2 and m3 is
𝒎𝟐 𝒎𝟑
1 𝑻 2 𝑻
𝒎𝟏 + 𝒎𝟐 + 𝒎𝟑 𝒎𝟏 + 𝒎𝟐 + 𝒎𝟑
𝒎𝟏 + 𝒎𝟐 𝒎𝟐 + 𝒎𝟑
3 𝑻 4 𝑻
𝒎𝟏 + 𝒎𝟐 + 𝒎𝟑 𝒎𝟏 + 𝒎𝟐 + 𝒎𝟑

Ans (3)
 Question

Three blocks of masses m1, m2 and m3 are connected by massless strings as shown
on a frictionless table. They are pulled with a force
T3= 40 N. If m1 = 10 kg, m2 = 6kg and m3 = 4kg, the tension T2 will be

1 20 N

2 40 N

3 10 N

4 32 N

Ans (4)
 Question

A block of mass m1 rests on a horizontal table. A string tied to the block is passed
on a frictionless pulley fixed at the end of the table and to the other end of string
is hung another block of mass m2. The acceleration of the system is

𝒎𝟐 𝒈
1
𝒎𝟏 + 𝒎𝟐

𝒎𝟏 𝒈
2
𝒎𝟏 𝒉 + 𝒎𝟐

3 g

𝒎𝟐 𝒈
4
𝒎𝟏
Ans (1)
 Question

A 2 kg block is lying on a smooth table which is connected by a body of mass 1 kg

by a string which passes through a pulley. The 1 kg mass is hanging vertically.
The acceleration of block and tension in the string will be

1 3.27 m/s2, 6.54 N

2 4.38m/s2, 6.54 N

3 3.27 m/s2, 9.86 N

4 4.38m/s2, 9.86 N

Ans (1)
 Question

Block B of mass 2 kg rests on block A of mass 10 kg. All surface are rough with the
values of coefficient of friction as shown in the figure. Find the minimum force F
that should be applied on block A to cause relative motion between A and B.
(g = 10 m/s2)

1 24 N

2 30 N

3 48 N

4 60 N

Ans (4)
 Question

Two blocks A and B are as shown in figure. The minimum horizontal force F
applied on block ‘B’ for which slipping begins at ‘B’ and ground is:

1 100 N

2 120 N

3 50 N

4 140 N

Ans (1)
 Question

In given diagram what is the minimum value of a horizontal external force F on

Block ‘A’ so that block ‘B’ will slide on ground is:

1 30 N

2 20 N

3 10 N

4 Not possible

Ans (4)
 Question

In the previous question the minimum force ‘F’ required, so that block ‘A’ will slip
on block ‘B’ is:

1 30 N

2 20 N

3 10 N

4 Not possible

Ans (2)
 Question

Two blocks A(1 kg) and B(2 kg) are connected by a string passing over a smooth
pulley as shown in the figure. B rests on rough horizontal surface and A rest on B.
The coefficient of friction between A and B is the same as that between B and the
horizontal surface. The minimum horizontal force F required to move A and to the
left is 25 N. The coefficient of friction is: [g = 10 m/s2]

1 0.67

2 0.5

3 0.4

4 0.25
Ans (2)
 Question

In which of the following cases the friction force between ‘A’ and ‘B’ is maximum.
In all case μ1 = 0.5, μ2 = 0.

1 2

3 4

Ans (2)
 Question

In the situation shown in figure a wedge of mass m is placed on a rough surface, on

which a block of equal mass is placed on the inclined plane of wedge. Friction
coefficient between plane and the block and the ground and the wedge (μ).
An external force F is applied horizontally on the wedge. Given that m does not
slide on incline due to its weight. The value of F at which wedge will start slipping
is:
1 = μ mg

2 = (3/2)μ mg

3 > 2μ mg

4 < μ mg
Ans (3)
 Question

In the situation shown in figure a wedge of mass m is placed on a rough surface, on

which a block of equal mass is placed on the inclined plane of wedge. Friction
coefficient between plane and the block and the ground and the wedge (μ). An
external force F is applied horizontally on the wedge. Given that m does not slide
on incline due to its weight. The value of F at which no friction will act between
block and inclined plane, is

1 2μ mg

2 2μ mg + 2mg tanθ

3 2μ mg + mg tanθ

4 2μ mg + mg sinθ Ans (2)

 Question

In the situation shown in figure a wedge of mass m is placed on a rough surface, on

which a block of equal mass is placed on the inclined plane of wedge. Friction
coefficient between plane and the block and the ground and the wedge (μ).
An external force F is applied horizontally on the wedge. Given that m does not
slide on incline due to its weight. The minimum value of acceleration of wedge for
which the block starts sliding on the wedge is:
𝐜𝐨𝐬 𝛉 + 𝛍 𝐬𝐢𝐧 𝛉 𝐬𝐢𝐧 𝛉 + 𝛍 𝐜𝐨𝐬 𝛉
1 𝒈 2 𝒈
𝐬𝐢𝐧 𝛉 − 𝛍 𝐜𝐨𝐬 𝛉 𝐜𝐨𝐬 𝛉 − 𝛍 𝐬𝐢𝐧 𝛉

𝐬𝐢𝐧 𝛉 − 𝛍 𝐜𝐨𝐬 𝛉 𝐜𝐨𝐬 𝛉 − 𝛍 𝐬𝐢𝐧 𝛉

3 𝒈
𝐬𝐢𝐧 𝛉 + 𝛍 𝐜𝐨𝐬 𝛉 4 𝒈
𝐜𝐨𝐬 𝛉 + 𝛍 𝐬𝐢𝐧 𝛉

Ans (2)
 Question

Three blocks A, B and C of equal mass m are placed one over other on a
frictionless surface (table) as shown in the figure. Coefficient of friction between
any blocks A, B and C is μ. The maximum value of mass of block MD so that the
block A, B and C move without slipping over each other is

𝟑𝒎𝛍 𝟑𝒎 𝟏 − 𝛍
1 2
𝛍+𝟏 𝛍
𝟑𝒎 𝟏 + 𝛍 𝟑𝒎𝛍
3 4
𝛍 𝟏−𝛍

Ans (4)
 Question

The rear side of a truck is open and a box of mass 20 kg is placed on the truck 4 m
away from the open end, μ = 0.15 and g = 10 m/s2. The truck start from rest with
an acceleration of 2m/s2 on a straight road. The distance moved by the truck
when box start fall down is:-

1 4m

2 8m

3 16 m

4 32 m

Ans (3)
 Question

In the arrangement shown in the figure, mass of the block B and A is 2m and m
respectively. Surface between B and floor is smooth. The block B is connected to
the block C by means of a string-pulley system. If the whole system is released, the
find the minimum value of mass of block C so that A remains stationary w.r.t.
B Coefficient of friction between A and B is μ.

1 m/μ

2 (2m+1)/(μ+1)

3 3m/(μ−1)

4 6m/(μ+1)
Ans (3)
 Question

A block of mass m1 = 1 kg another mass m2 = 2 kg, are placed together (see figure)
on an inclined plane with angle of inclination θ. Various values of θ are given in
List I. The coefficient of friction between the block m1 and the plane is always
zero. The coefficient of static and dynamic friction between the block m2 and the
plane are equal to μ = 0.3. In List II expressions for the friction on block m2 are
given. Match the correction expression of the friction in List II with the angles
given in List I, and choose the correct option. The acceleration due to gravity is
denoted by g. [useful information : tan(5.5°) ≈ 0.1; tan (11.5°) ≈ 0.2;
tan(16.5°) ≈ 0.3]
 P Q R S
1 1 1 1 3
List-I List-II
2 2 2 2 3
(P) θ = 5° (1) m2gsinθ
(Q) θ = 10° (2) (m1 + m2)g sinθ
3 2 2 2 4 (R) θ = 15° (3) μm2gcosθ
(S) θ = 20° (4) μ(m1 + m2)g cosθ
4 2 2 3 3

Ans (4)
 Question

A block A is placed over a long rough plank B of same mass as shown in figure.
The plank is placed over a smooth horizontal surface. At time t = 0, block A is
given a velocity v0 in horizontal direction. Let v1 and v2 be the velocities of A and B
at time t. Then choose the correct graph between v1 or v2 and t.

1 2

3 4

Ans (2)
 Question

The three flat blocks in the figure are positioned on the 37° incline and a force
parallel to the inclined plane is applied to the middle block. The upper block is
prevented from moving by a write which attaches it to the fixed support.
The masses of three blocks in kg and coefficient of static friction for each of the
three pairs of contact surfaces is shown in the figure. Determine the maximum
values which force P may have before slipping take place anywhere.
1 10 N

2 9N

3 12 N

4 8N
Ans (3)
 Question

Figure shows two block system, 4 kg block rests on a smooth horizontal surface,
upper surface of 4 kg is rough. A block of mass 2 kg is placed on its upper surface.
The acceleration of upper block with respect to earth when 4 kg mass is pulled by
a force of 30 N, is.

1 6 m/s2

2 5 m/s2

3 8 m/s2

4 2 m/s2

Ans (2)
 Question

The frictional force acting on 1 kg block is

1 0.1 N

2 2N

3 0.5 N

4 5N

Ans (1)
 Question

Block A weighing 100 kg rests on a block B and is tied with a horizontal string to
the wall at C. Block B weighs 200 kg. The coefficient of friction between A and B is
0.25 and between B and the surface is 1/3. The horizontal force P necessary to
move the block B should be (g = 10 m/s2)

1 1150 N

2 1250 N

3 1300 N

4 1420 N

Ans (2)
 Question

What is the friction force acting on the upper block when the system of two blocks
moves with an acceleration of 4 m/s2?

1 20 N

2 16 N

3 12 N

4 Zero

Ans (2)
 Question

For what value of force F, the mass 2 kg starts its motion in left direction relative to
5 kg [Take g = 10 m/s2]

1 4N

2 10 N

3 14 N

4 7N

Ans (3)
 Question

The friction force acting between 10 kg block and surface is [Take g = 10 m/s2]

1 60 N

2 5N

3 20 N

4 30 N

Ans (2)
 Question

In the given figure a force of 24 N acts on the upper block, then find friction acting
on 4 kg block. (g = 10 m/s2)

1 20 N

2 16 N

3 12 N

4 14.5 N

Ans (2)
 Question

A body of mass 100 g is sliding on a inclined plane with an inclination of 60°. What
is the frictional force experienced, if coefficient of friction is 1.7 ? (Take g = 10
m/s2)

1 0.85 N

2 0.95 N

3 1.05 N

4 1.145 N

Ans (1)
 Question

A block of mass m is placed on a smooth inclined wedge ABC of inclination θ as

shown in the figure. The wedge is given an acceleration ‘a’ towards the right.
The relation between a and θ for the block to remain stationary on the wedge is:-
𝒈
1 a=
cosec𝜽
𝒈
2 a=
𝒔𝒊𝒏 𝜽

3 a = g cos θ

4 a = g tan θ

Ans (4)
 Question

A block of mass m is in contact with the cart C as shown in the figure.

The coefficient of static friction between the block and the cart is µ. The
acceleration a of the cart that will prevent the block from falling satisfies:-
𝐦𝐠
1 𝛂>
𝛍
𝐠
2 𝛂>
𝛍𝐦
𝐠
3 𝛂≥
𝛍
𝐠
4 𝛂<
𝛍

Ans (3)
 Question

A block of mass m is placed on a smooth wedge of inclination θ. The whole system

is accelerated horizontally so that the block does not slip on the wedge. The force
exerted by the wedge on the block will be (g is acceleration due to gravity)

1 mg cos θ

2 mg sin θ

3 mg

4 mg/cos θ

Ans (4)
 Question

A stone of mass 0.5 kg tied with a string of length 1 metre is moving in a circular
path with a speed of 4 m/sec. The tension acting on the string in Newton is

1 2

2 8

3 0.2

4 0.8

Ans (2)
 Question

If the radii of circular paths of two particles of same masses are in the ratio of
1 : 2, then in order to have same centripetal force, their speeds should be in the
ratio of :

1 1:4

2 4:1

3 1 : √2

4 √2 : 1

Ans (3)
 Question

A car is moving on a plane inclined at 30° to the horizontal with an acceleration of

10 m/s2 parallel to the plane upward. A bob is suspended by a string from the
roof. The angle in degrees which the string makes with the vertical is: (Assume
that the bob does not move relative to car) [g = 10 m/s2]

1 20°

2 30°

3 45°

4 60°

Ans (2)
 Question

A wedge of height 'h' is released from rest with a light particle P placed on it as
shown. The wedge slides down an incline which makes an angle θ with the
horizontal. All the surfaces are smooth. P will reach the surface of incline in time:

𝟐𝒉 𝟐𝒉
1 2
𝒈 sin𝟐 𝛉 𝒈 sin𝛉cos 𝛉

𝟐𝒉 𝟐𝒉
3 4
𝒈 tan 𝛉 𝒈 cos2 𝛉

Ans (1)
 Question

A cylinder rests in a supporting carriage as shown. The side AB of carriage makes an

angle 30° with the horizontal and side BC is vertical. The carriage lies on a fixed
horizontal surface and is being pulled towards left with a horizontal acceleration 'a'. The
magnitude of normal reactions exerted by sides AB and BC of carriage on the cylinder be
NAB and NBC respectively (Neglect friction everywhere). Then as the magnitude on
acceleration 'a' of the carriage is increased, pick up the correct statement:

1 NAB increases and NBC decreases

2 Both NAB and NBC increase

3 NAB remains constant and NBC increases

4 NAB increases and NBC remains constant

Ans (3)
 Question

A conveyor belt is moving at a constant speed of 2 m/s, a box is gently dropped on

it. The coefficient of friction between them is 0.5. The distance that the box will
move relative to belt before coming to rest on it (taking g = 10 ms–2), is

1 1.2 m

2 0.6 m

3 zero

4 0.4 m

Ans (4)
 Question

Adjoining figure shows two blocks A and B pushed against the wall with a force F.
The wall is smooth but the surfaces in contact of A and B are rough. Which of the
following is true for the system of blocks to be at rest against the wall?

1 F should be more than the weight of A and B

2 F should be equal to the weight of A and B

3 F should be less than the weight of A and B

4 System cannot be in equilibrium

Ans (4)
 Question

How much Pseudo force will act on a mass of 3 kg as observed from a reference
from of person of 5 kg moving with acceleration of 2 m/s2 in right direction?

1 10 N toward left

2 10 N towards right

3 6N towards right

4 6 N towards left

Ans (4)
 Question

Pseudo force, also called fictitious force, such as centrifugal force, arises only in

1 Inertial frames

2 Non-inertial frames

3 Both inertial and non-inertial frames

4 Rigid frames

Ans (2)
 Question

A mass of 100 g is tied to one end of a string 2 m long. The body is revolving in a
horizontal circle making a maximum of 200 rev min–1. The other end of the string
is fixed at the centre of the circle of revolution. The maximum tension that the
string can bear is (approximately)

1 8.76 N

2 8.94 N

3 84.42 N

4 87.64 N

Ans (4)
 Question

A car is taking turn on a circular path of radius R. If the coefficient of friction

between the tyres and road is μ, the maximum velocity for no slipping is

1 μRg

2 2 μRg

3 (μRg)1/2

4 (2 μRg)1/2

Ans (3)
 Question

A car is moving in a circular horizontal track of radius 10 m with a constant speed

of 10 ms–1. A plumb bob is suspended from the roof of the car by a light rigid rod
of length 1 m. The angle made by the rod with track is

1 Zero

2 30°

3 45°

4 60°

Ans (3)
 Question

A car of mass 1000 kg negotiates a banked curve of radius 90 m on a frictionless

road. If the banking angle is 45°, the speed of the car is

1 20 ms–1

2 30 ms–1

3 5 ms–1

4 10 ms–1

Ans (2)
 Question

A block of mass m at the end of a string is whirled round in a vertical circle of

radius R. The critical speed of the block at top of its swing below which the string
would slacken before the block reaches the bottom is?

1 𝟓𝑹𝒈

2 𝟑𝑹𝒈

3 𝟐𝑹𝒈

4 𝑹𝒈

Ans (4)
 Question

A stone is attached to one end of a string and rotated in a vertical circle. If string
breaks at the position of maximum tension, it will break at

1 A

2 B

3 C

4 D

Ans (1)
 Question

A particle of mass m is being circulated on a vertical circle of radius r. If the speed

of particle at the highest point be v, then
𝒎𝒗𝟐
1 𝒎𝒈 =
𝒓
𝒎𝒗𝟐
2 𝒎𝒈 >
𝒓
𝒎𝒗𝟐
3 𝒎𝒈 ≤
𝒓
𝒎𝒗𝟐
4 𝒎𝒈 ≥
𝒓

Ans (3)
 Question

A particle of mass m is circulating on a circle of radius r having angular

momentum L about centre. Then, the centripetal force will be
𝑳𝟐
1
𝒎𝒓
𝑳𝟐
2
𝒎𝒓𝟐
𝑳𝟐
3
𝒎𝒓𝟑
𝑳
4
𝒎𝒓𝟐

Ans (3)
 Question

A particle of mass 2 kg is moving along a circular path of radius 1 m. If its angular

speed is 2π rad s–1, the centripetal force on it is

1 4 πN

2 8 πN

3 4 π4N

4 8 π2N

Ans (4)
 Question

Two particles of equal masses are revolving in circular paths of radii r1 and r2
respectively with the same speed. The ratio of their centripetal forces is

𝒓𝟐 𝒓𝟐
1 2
𝒓𝟏 𝒓𝟏
𝟐 𝟐
𝒓𝟏 𝒓𝟐
3 4
𝒓𝟐 𝒓𝟏

Ans (1)
 Question

A particle of mass m is executing uniform circular motion on a path of radius r. If p

is the magnitude of its linear momentum. The radial force acting on the particle is

1 pmr

2 rm/p

3 (mp2)/r

4 p2/rm

Ans (4)
 Question

A stone of mass of 16 kg is attached to a string 144 m long and is whirled in a

horizontal circle on a smooth surface. The maximum tension the string can
withstand is 16 N. The maximum velocity of revolution that can be given to the
stone without breaking it, will be

1 20 ms–1

2 16 ms–1

3 14 ms–1

4 12 ms–1

Ans (4)
 Question

A motorcycle is going on an overbridge of radius R. The driver maintains a

constant speed. As the motorcycle is ascending on the overbridge, the normal
force on it

1 Increase

2 Decease

3 Remains the same

4 Fluctuates

Ans (1)
 Question

A point mass m is suspended from a light thread of length l, fixed at O, is which in a

horizontal circle at constant speed as shown. From your point of view, stationary
with respect to the mass, the forces on the mass are

1 2

3 4

Ans (3)
 Question

A particle describes a horizontal circle in a conical funnel whose inner surface is

smooth with speed of 0.5 m/s. What is the height of the plane of circle from vertex
of the funnel?
1 0.25 cm

2 2 cm

3 4 cm

4 2.5 cm

Ans (4)
 Question

A stone of mass 0.1 kg tied to one end of a string 1.0 m long is revolved in
horizontal circle at the rate of 10/π revolution per second. Calculate the tension of
the string?

1 30 N

2 40N

3 50N

4 60N

Ans (2)
 Question

A string of length 1 = 1 m is fixed at one end and carries a mass of 100 gm at other
end. The string makes 𝟓/ revolutions per second about a vertical axis passing
through its second end. What is the angle of inclination of the string with the
vertical?

1 30°

2 45°

3 60°

4 75°

Ans (3)
 Question

A car of mass 1000 kg moves on a circular path with constant speed of 16 m/s. It is
turned by 90° after traveling 628 m on the road. The centripetal force acting on
the car is-

1 160 N

2 320 N

3 640 N

4 1280 N

Ans (3)
 Question

A cyclist is moving on a circular track of radius 80 m with a velocity of 72 km/hr.

He has to learn from the vertical approximately through an angle

1 tan–1(1/4)

2 tan–1(1)

3 tan–1(1/2)

4 tan–1(2)

Ans (3)
 Question

A road is banked at an angle of 30° to the horizontal for negotiating a curve of

radius 10 𝟑 m. At what velocity will a car experience no friction while negotiating
the curve?

1 54 km/hr

2 72 km/hr

3 36 km/hr

4 18 km/hr

Ans (3)
 Question

A cyclist taking turn bends inwards while a car passenger take the same turn is
thrown outwards. The reason is-

1 Car is heavier then cycle

2 Car has four wheels while cycle has only two

3 Difference in the speed of the two

4 Cyclist has to counteract the centrifugal force while in the case of car only the
passenger is thrown by the force

Ans (4)
 Question

A car is negotiating a curved road of radius r. If the coefficient of friction between

the tyres and the road is μ, the car will skid if its speed exceeds

1 𝛍𝒓𝒈

2 𝛍𝒖𝒓𝒈

3 𝟑𝛍𝒓𝒈

4 𝟐 𝛍𝒓𝒈

Ans (1)
 Question

A car turns a corner on a slippery road at a constant speed of 12 m/s. If the

coefficient of friction is 0.4, the minimum radius of the arc in metres in which the
car turns is

1 72

2 36

3 18

4 9

Ans (2)
 Question

A motor cycle driver doubles its velocity when he is taking a turn. The force
exerted towards the centre will become:-

1 double

2 half

3 4 times

4 1/4times

Ans (3)
 Question

A 500 kg car takes a round turn of radius 50 m with a velocity of 36 km/hr.

The centripetal force is:-

1 250 N

2 1000 N

3 750 N

4 1200 N

Ans (2)
 Question

The force required to keep a body in uniform circular motion is :-

1 Centripetal force

2 Centrifugal force

3 Resistance

4 None of the above

Ans (1)
 Question

The earth (Me = 6 × 1024 kg) is revolving round the sun in an orbit of radius
(1.5 × 108) km with angular velocity of (2 × 10–7) rad/s. The force (in newton)
exerted on the earth by the sun will be:-

1 36 × 1021

2 16 × 1024

3 25 × 1016

4 Zero

Ans (1)
 Question

A string of length 10 cm breaks if its tension exceeds 10 newton. A stone of mass

250 g tied to this string, is rotated in a horizontal circle. The maximum angular
velocity of rotation can be:-

1 20 rad/s

2 40 rad/s

3 100 rad/s

4 200 rad/s

Ans (1)
 Question

In uniform circular motion, the velocity vector and acceleration vector are

1 Perpendicular to each other

2 Same direction

3 Opposite direction

4 Not related to each other

Ans (1)
 Question

A 0.5 kg ball moves in a circle of radius 0.4 m at a speed of 4 m/s. The centripetal
force on the ball is:-

1 10 N

2 20 N

3 40 N

4 80 N

Ans (2)
 Question

The radius of the circular path of a particle is doubled but its frequency of
rotation is kept constant. If the initial centripetal force be F, then the final value of
centripetal force will be :-

1 F

2 F/2

3 4F

4 2F

Ans (4)
 Question

The angular acceleration of particle moving along a circular path with uniform
speed is:

1 Uniform but non zero

2 Zero

3 Variable

4 Cannot be predicted from given information

Ans (2)
 Question

If the speed and radius both are trippled for a body moving on a circular path,
then the new centripetal force will be:-

1 Doubled of previous value

2 Equal to previous value

3 Triple of previous value

4 One third of previous value

Ans (3)
 Question

When a body moves with a constant speed along a circle:-

1 No acceleration is present in the body

2 No force acts on the body

3 Its velocity remains constant

4 No work gets done on it

Ans (4)
 Question

A gramophone record is revolving with an angular velocity ω. A coin is placed at a

distance r from the centre of the record. The static coefficient of friction is µ.
The coin will revolve with the record if:-
𝛍𝒈
1 𝒓≥ 𝟐
𝛚
2 𝒓 = 𝛍𝒈𝛚𝟐
𝛚𝟐
3 𝒓<
𝛍𝒈
𝛍𝒈
4 𝒓≤ 𝟐
𝛚

Ans (4)
 Question

A car of mass 1000 kg negotiates a banked curve of radius 90 m on a frictionless

road. If the banking angle is 45°, the speed of the car is:-

1 5 m/s

2 10 m/s

3 20 m/s

4 30 m/s

Ans (4)
 Question

A car of mass m is moving on a level circular track of radius R. If μs represents the

static friction between the road and tyres of the car, the maximum speed of the car
in circular motion is given by:-
𝒎𝑹𝒈
1
𝛍𝒔

2 𝛍𝒔 𝑹𝒈

3 𝛍𝒔 𝒎𝑹𝒈

𝑹𝒈
4
𝛍𝒔

Ans (2)
 Question

Two stones of masses m and 2 m are whirled in horizontal circles, the heavier one
𝒓
in a radius and the lighter one in radius r. The tangential speed of lighter stone is
𝟐
n times that of the value of heavier stone when they experience same centripetal
forces. The value of n is:
1 1

2 2

3 3

4 4

Ans (2)
 Question

A small sphere is suspended by a sting from the ceiling of a car. If the car begins to
𝒈
move with a constant acceleration , the inclination of the string to the vertical is:-
𝟐
𝟏
1 𝐭𝐚𝐧–𝟏
𝟐
in the direction of motion

𝟏
2 𝐭𝐚𝐧–𝟏
𝟐
opposite to the direction of motion

3 tan–1(2) in the direction of motion

4 tan–1(2) opposite to the direction of motion

Ans (2)
 Question

Find velocity of block B?

1 10 m/s

2 15 m/s

3 20 m/s

4 25 m/s

Ans (1)
 Question

Find out the velocity of block B in a pulley block system as shown in figure.

1 10/2 m/sec

2 15/2 m/sec

3 20/2 m/sec

4 None of these

Ans (2)
 Question

Find velocity of block A

1 5 m/s

2 8 m/s

3 10 m/s

4 15 m/s

Ans (3)
 Question

Find velocity of block A

1 Va = 20 m/s–1 (downward direction)

2 Va = 20 m/s–1 (upward direction)

3 Va = 30 m/s–1 (upward direction)

4 Va = 30 m/s–1 (downward direction)

Ans (2)
 Question

Find out the velocity of block D.

1 VD = 22 m/s (upward direction)

2 VD = 22 m/s (downward direction)

3 VD = 23 m/s (upward direction)

4 VD = 23 m/s (downward direction)

Ans (3)
 Question

Find the velocity of point G.

1 70 m/s upwards

2 70 m/s downwards

3 50 m/s upwards

4 50 m/s downwards

Ans (1)
 Question

1 VC = 14 m/sec (upward)

2 VC = 14 m/sec (downward)

3 VC = 15 m/sec (upward)

4 VC = 15 m/sec (downward)

Ans (1)
 Question

1 VE = 30/2 m/s upward

2 VE = 30/2 m/s downward

3 VE = 31/2 m/s upward

4 VE = 31/2 m/s downward

Ans (3)
 Question

Find the velocity of the hanging block if the velocities of the free ends of the rope
are as indicated in the figure.

1 3/2 m/s ↑

2 3/2 m/s ↓

3 1/2 m/s ↑

4 1/2 m/s ↓

Ans (1)
 Question

Find velocity of block ‘B’ at the instant shown in figure.

1 25 m/s

2 22 m/s

3 20 m/s

4 30 m/s

Ans (1)
 Question

In the figure shown the velocity of different blocks is shown. The velocity of C is

1 6 m/s

2 4 m/s

3 0 m/s

4 None of these

Ans (2)
 Question

Find velocity of ring B (VB) at the instant shown. The string is taut and
inextensible.

1 1/2 m/s

2 √3/4 m/s

3 1/4 m/s

4 1 m/s

Ans (4)
 Question

The 50 kg homogenous smooth sphere rests on the 30° incline A and bears against
the smooth vertical wall B. Calculate the contact forces at A and B.
𝟏𝟎𝟎𝟎 𝟓𝟎𝟎
1 𝑵𝑩 = 𝑵, 𝑵𝑨 = 𝑵
𝟑 𝟑
𝟏𝟎𝟎𝟎 𝟓𝟎𝟎
2 𝑵𝑨 = 𝑵, 𝑵𝑩 = 𝑵
𝟑 𝟑
𝟏𝟎𝟎 𝟓𝟎
3 𝑵𝑨 = 𝑵, 𝑵𝑩 = 𝑵
𝟑 𝟑
𝟏𝟎𝟎𝟎 𝟓𝟎
4 𝑵𝑨 = 𝑵, 𝑵𝑩 = 𝑵
𝟑 𝟑

Ans (2)
 Question

The pulleys in the diagram are all smooth and light. The acceleration of A is a
upwards and the acceleration of C is f downwards. The acceleration of B is:

1 1/2 (f – a) up

2 1/2 (a + f) down

3 1/2 (a + f) up

4 1/2 (a – f) up

Ans (1)
 Question

If acceleration of A is 2 m/s2 to left and acceleration of B is 1 m/s2 to left, then

acceleration of C is

1 1 m/s2 upwards

2 1 m/s2 downwards

3 2 m/s2 downwards

4 2 m/s2 upwards

Ans (1)
 Question

If block A has a velocity of 0.6 m/s to the right determine the velocity of block B.

1 1.8 m/s in downward direction

2 1.8 m/s in upward direction

3 0.6 m/s in downward direction

4 0.6 m/s in upward direction

Ans (1)
 Question

Block B moves to the right with a constant velocity v0. The velocity of body A
relative to B is:

1 v0/2, towards left

2 v0/2, towards right

3 (3v0)/2 towards left

4 (3v0)/2 towards right

Ans (2)
 Question

Find the acceleration of C w.r.t ground.

1 𝒂𝒊Ƹ − (𝟐𝒂 + 𝟐𝒃)𝒋Ƹ

2 𝒂𝒊Ƹ − (𝟐𝒂 + 𝒃)𝒋Ƹ

3 𝒂𝒊Ƹ − (𝒂 + 𝟐𝒃)𝒋Ƹ

4 𝒃𝒊Ƹ − (𝟐𝒂 + 𝟐𝒃)𝒋Ƹ

Ans (1)
 Question

Find the acceleration of B

𝒂 𝐜𝐨𝐬 𝛂𝟏 𝒂 𝐬𝐢𝐧 𝛂𝟏
1 2
𝐜𝐨𝐬 𝛂𝟐 𝐜𝐨𝐬 𝛂𝟐
𝒂 𝐜𝐨𝐬 𝛂𝟐 𝐜𝐨𝐬 𝛂𝟏
3 4
𝐜𝐨𝐬 𝛂𝟏 𝐜𝐨𝐬 𝛂𝟐

Ans (1)
 Question

In the arrangement shown, the pulleys and the strings are ideal. The acceleration
of block B is

1 g/5

2 g/2

3 2g/5

4 2g/3

Ans (3)
 Question

Block A and B have masses 2 kg and 3 kg respectively. The ground is smooth. P is

an external force of 10 N. The force exerted by B on A is

1 6N

2 4N

3 3N

4 1N

Ans (1)
 Question

The velocity of end ‘A’ of rigid rod placed between two smooth vertical walls
moves with velocity ‘u’ along vertical direction. Find out the velocity of end ‘B’ of
that rod, rod always remains in constant with the vertical walls.

1 u tan 2θ

2 u cot θ

3 u tan θ

4 2u tan θ

Ans (3)
 Question

Three blocks 1, 2 and 3 are arranged as shown in the figure. The velocities of the
blocks v1, v2 and v3 are shown in the figure. What is the relationship between v1, v2.
and v3?

1 2v1 + v2 = v3

2 v1 + v2 = v3

3 v1 + 2v2 = v3

4 None of these

Ans (4)
 Question

A block of mass m is placed on a horizontal surface with  as the coefficient of

static friction between the body and the surface. It is kept in equilibrium by a
weight w and the tension T in a string. The value of  is equal to.

1 w/mg

2 mg/√3

3 w/(√3 mg)

4 mg/3

Ans (3)
 Question

A heavy uniform chain lies on a horizontal table top. If the coefficient of friction
between the chain and the table surface is 0.2, what is the maximum fraction of
the length of the chain that can hang down the table-

1 1/6

2 1/4

3 1/3

4 1/2

Ans (1)
 Question

A force of 12N acts on a body of mass 4kg projected on a rough surface (coefficient
of friction is 0.2, g = 10ms–2). The acceleration of the body in ms–2 is-

1 1

2 0.5

3 0.25

4 zero

Ans (1)
 Question

A body is sliding down an inclined plane forming an angle of 30° with the
horizontal. If the coefficient of friction is 0.3, then acceleration of the body is-

1 1.25ms–2

2 2.3ms–2

3 3.4ms–2

4 4.9ms–2

Ans (2)
 Question

Find the minimum force required to pull the lower block. If the coefficient of
friction between the blocks is 0.1 and between the ground and 2kg block is 0.2
(g = 10ms–2)

1 1N

2 5N

3 7N

4 10N

Ans (3)
 Question

A book sits on horizontal top of a car as the car accelerates horizontally from rest.
If the static coefficient of friction between car top and the book is 0.45, the
maximum acceleration the car can have for the book not to slip is-

1 3.92 ms–2

2 4.41 ms–2

3 4.9 ms–2

4 9.8 ms–2

Ans (2)
 Question

A force of 𝟑 𝟑 kg wt is just sufficient to pull a block of 9 kg wt over a flat surface.

The coefficient of friction is.

1 √3

2 1/√3

3 1/2

4 √2

Ans (2)
 Question

A car running with a velocity 72 kmph on a level road, is stopped after travelling a
distance of 30m after disengaging its engine (g = 10ms–2). The coefficient of
friction between the road and the tyres is

1 0.33

2 4.5

3 0.67

4 0.8

Ans (3)
 Question

A block of mass m is placed on a smooth wedge of inclination . The whole system

is accelerated horizontally so that the block does not slip down. The force exerted
by the wedge on the block is

1 mg/sinθ

2 mg/cosθ

3 mgcosθ

4 mgsinθ

Ans (2)
 Question

A block of mass 1 kg rests on a rough inclined plane making an angle of 30° with
the horizontal. If s = 0.5 and k = 0.4, the frictional force on the block is

1 𝟏. 𝟗𝟕𝟔 𝟑𝑵

𝟑
2 𝟎. 𝟒 × 𝟗. 𝟖 𝑵
𝟐

3 𝟗. 𝟖 × 𝟑𝑵

4 0.4 × 5 9.8 N

Ans (2)
 Question

A book of weight 20N is pressed between two hands and each hand exerts a force
of 40N. If the book just starts to slide down, then Coefficient of friction is

1 0.25

2 0.2

3 0.5

4 0.1

Ans (1)
 Question

A force of 50 N acting on a body of mass 200 kg produce uniform velocity. If the

force is tripled, then the acceleration produced is.

1 0.5 ms–2

2 0.3 ms–2

3 0.8 ms–2

4 0.4 ms–2

Ans (1)
 Question

Two bodies having the same mass, 2 kg each have different surface areas 20 m2
and 100 m2 in contact with a horizontal surface. If the coefficient of friction is
0.2, the forces of friction that come into play when they are in motion. Find the
ratio of frictional forces.

1 2:1

2 1:2

3 3:1

4 1:1

Ans (4)
 Question

In the figure given, the system is in equilibrium. What is the maximum value that
W can have if the friction force on the 40N block cannot exceed 12.0 N

1 3.45 N

2 6.92 N

3 10.35 N

4 12.32 N

Ans (2)
 Question

Consider the following statements and select the incorrect statements (s)
(I) To move a football at rest, some one must kick it.
(II) To throw a stone upwards, one has to give it an upward push.
(III) A breeze causes the branches of a tree to become stationary.
(IV) A strong wind can move even heavy objects.

1 Only I

2 Only III

3 III and IV

4 I and II
Ans (2)
 Question

Which of the following statements is/are incorrect, when a person walks on a

rough surface?
(I) The frictional force exerted by the surface keeps him moving
(II) The force which the man exerts on the floor keeps him moving
(III) The reaction of the force which the man exerts on floor keeps him moving

1 I only

2 II only

3 I and III

4 I and II
Ans (2)
 Question

Select the wrong statement(s) from the following.

(I) Newton’s laws of motion hold good for both inertial and non-inertial frames
(II) During explosion, linear momentum is conserved
(III) Force of friction is zero when no driving force is applied

1 I only

2 II only

3 I and II

4 II and III

Ans (1)
 Question

Select the incorrect statement(s) about static friction.

(I) Static friction exists on its own
(II) In the absence of applied force static friction is maximum
(III) Static friction is equal and opposite to the applied force upto a certain limit

1 I only

2 II and III

3 I and III

4 I and II

Ans (4)
 Question

Select the incorrect statement(s) from the following.

(I) Limiting friction is always greater than the kinetic friction
(II) Limiting friction is always less than the static friction
(III) Coefficient of static friction is always greater than the coefficient of kinetic
friction

1 I only

2 I and III

3 II only

4 I and II
Ans (3)
 Question

Assertion : On a rainy day, it is difficult to drive a car or bus at high speed.

Reason : The value of coefficient of friction is lowered due to wetting of the
surface.

1 Assertion is correct, reason is correct; reason is a correct explanation for

assertion.

2 Assertion is correct, reason is correct; reason is not a correct explanation

for assertion

3 Assertion is correct, reason is incorrect

4 Assertion is incorrect, reason is correct.

Ans (1)
 Question

Assertion : Static friction is self adjusting force.

Reason : The magnitude of friction is equal to the applied force and its direction
is opposite to that of the applied force.

1 Assertion is correct, reason is correct; reason is a correct explanation for

assertion.

2 Assertion is correct, reason is correct; reason is not a correct explanation

for assertion

3 Assertion is correct, reason is incorrect

4 Assertion is incorrect, reason is correct.

Ans (3)
 Question

Assertion : Angle of repose is equal to angle of limiting friction.

Reason : When the body is just at the point of motion, the force of friction in this
stage is called as limiting friction.

1 Assertion is correct, reason is correct; reason is a correct explanation for

assertion.

2 Assertion is correct, reason is correct; reason is not a correct explanation

for assertion

3 Assertion is correct, reason is incorrect

4 Assertion is incorrect, reason is correct.

Ans (2)
 Question

Assertion : Friction is a necessary evil

Reason : Though friction dissipates power, but without friction we cannot walk.

1 Assertion is correct, reason is correct; reason is a correct explanation for

assertion.

2 Assertion is correct, reason is correct; reason is not a correct explanation

for assertion

3 Assertion is correct, reason is incorrect

4 Assertion is incorrect, reason is correct.

Ans (1)
 Question

Assertion : It is convenient to pull luggage fitted with rollers.

Reason : Rolling reduces friction. Rolling friction is less than sliding friction. It
is always easier to roll than to slide a body over another.
1 Assertion is correct, reason is correct; reason is a correct explanation for
assertion.

2 Assertion is correct, reason is correct; reason is not a correct explanation

for assertion

3 Assertion is correct, reason is incorrect

4 Assertion is incorrect, reason is correct.

Ans (1)
 Question

Match the column I with column II and select the correct option from the given
codes.
Column I Column II
1 A-q; B-r; C-s; D-p
(A) Static friction (p) is slightly less than
limiting friction
2 A-s; B-p; C-q; D-r
(B) Dynamic friction (q) Is maximum value
of static friction
3 A-r; B-q; C-p; D-s
(C) Limiting friction (r) Is equal to tangent
of angle of repose
4 A-s; B-p; C-r; D-q
(D) Coefficient of (s) is self-adjusting
friction

Ans (2)
 Question

Match the column I with column II and select the correct option from the given
codes.

1 (A)-(r), (B)-(p), (C)-(s), (D)-(q) Column I Column II

(A) Limiting (p) Self adjusting force
2 (A)-(s), (B)-(q), (C)-(p), (D)-(r) friction
(B) Static (q) Less than sliding
3 (A)-(r), (B)-(p), (C)-(q), (D)-(s) friction friction
(C) Dynamic (r) Maximum value of
4 (A)-(q), (B)-(p), (C)-(s), (D)-(r) friction static friction
(D) Rolling (s) Less than limiting
friction friction

Ans (1)
 Question

Match the column I with column II and select the correct option from the given
codes.
Column I Column II
1 (A)-(q), (B)-(p, q, r), (C)-(q), (D)-(p, q, r) (A) If friction force is less (p) Static
than applied force then
2 (A)-(q), (B)-(p, r), (C)-(q), (D)-(p, r) friction may be
(B) If friction force is equal (q) Kinetic
to the force applied,
3 (A)-(q), (B)-(p, q), (C)-(q), (D)-(p, q)
then friction may be
(C) If object is moving, then (r) Limiting
4 (A)-(q), (B)-( p, q, r), (C)-(s), (D)-(p, q, r) friction may be
(D) If object is at rest, then (s) No conclusion
friction may be. can be drawn

Ans (2)
 Question

The coefficient of friction between the block and the surface is 0.4 in Fig. (i-iv).
Match Column I with Column II
1 (A)-(q), (B)-(p), (C)-(p, q, r), (D)-(r)

2 (A)-(q), (B)-(r, s), (C)-(s), (D)-(p, s)

3 (A)-(p, r), (B)-(q, s), (C)-(p, q, r, s), (D)-(r, s)

4 (A)-(s), (B)-(p, q), (C)-(s), (D)-(r)

Column I Column II
(A) Force of friction is zero in (p) Fig. (i)
(B) Force of friction is 2.5 N in (q) Fig. (ii)
(C) Acceleration of the block is zero in (r) Fig. (iii)
(D) Normal force is not equal to 2g in (s) Fig. (iv)

Ans (3)
 Question

Match the column-I (type of friction) with column-II (value of ) and select the
correct option form the codes given below.

1 A-(s); B-(r); C-(p)

2 A-(p); B-(r); C-(q) Column I Column II

(A) Static friction (p)  is highest
3 A-(q); B-(r); C-(p) (B) Rolling friction (q)  is moderate
(C) Kinetic friction (r)  lowest
4 A-(s); B-(r); C-(q)

Ans (2)