DDP Physics
DDP Physics
Parishram 2026
Physics DPP: 2
Magnetism and Matter
Q1 The SI unit of magnetization (M) is: Q6 According to Curie's law, the magnetic
(A) A/m susceptibility (χ) of a paramagnetic material is:
(B) T (Tesla) (A) Directly proportional to temperature (T)
(C) A·m² (B) Inversely proportional to temperature (T)
(D) Wb/m (C) Independent of temperature
(D) Proportional to
Q2 Magnetic susceptibility (χ) is defined as
(A) The ratio of magnetic field (B) to Q7 A material has a permeability of 0.1 H/m when
magnetization (M) the magnetic intensity is 70 A/m. What will be
(B) The ratio of magnetization (M) to magnetic the magnetic induction inside the material?
field intensity (H) (A) 7 T (B) 0.7 T
(C) The product of magnetization (M) and (C) 70 T (D) 0.07 T
magnetic field intensity (H)
Q8 A material has a magnetization of
(D) The difference between magnetic field (B)
and magnetization (M) when subjected to a
magnetic field intensity of
Q3 The SI unit of magnetic permeability (μ) is
What is the magnetic susceptibility?
(A) H/m (henry per meter)
(A) 1.01 (B) 1.21
(B) T·m/A
(C) 1.41 (D) 1.61
(C) A/m
(D) Wb/m² Q9 A solenoid has a core material with a relative
permeability of 500. If the magnetic field
Q4 If the magnetic susceptibility of a material is χ,
intensity inside the solenoid is 1000 A/m, what
its relative permeability (μᵣ) is:
is the magnetic susceptibility of the core
(A)
material?
(B)
(A) 499 (B) 500
(C)
(C) 501 (D) 1000
(D)
Q10 Which of the following is a characteristic of
Q5 Diamagnetic materials are characterized by:
soft magnetic materials?
(A) Positive susceptibility
(A) High coercivity
(B) Negative susceptibility (B) High retentivity
(C) High permeability
(C) Low hysteresis loss
(D) Permanent magnetic moments (D) Used for making permanent magnet
Answer Key
Q1 A Q6 B
Q2 B Q7 A
Q3 A Q8 B
Q4 A Q9 A
Q5 B Q10 C
Q1 Text Solution:
The SI unit of magnetization (M) is ampere per
meter (A/m). Magnetization is defined as the
magnetic moment per unit volume of a
material. It's a vector quantity, meaning it has
both magnitude and direction
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Q2 Text Solution:
Magnetic susceptibility (χ) is a dimensionless
quantity that describes how easily a material
Q5 Text Solution:
can be magnetized when placed in an external
Negative susceptibility
magnetic field. It is defined as the ratio of the
magnetization (M) of the material to the Video Solution:
applied magnetic field intensity
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Q6 Text Solution:
Q3 Text Solution:
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Q7 Text Solution:
Magnetic induction (B) is given by the formula:
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Q10 Text Solution:
Soft magnetic materials, such as soft iron,
have low coercivity and low hysteresis loss,
making them ideal for applications like
transformer cores where rapid magnetization
and demagnetization are required
Q8 Text Solution:
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Magnetic susceptibility is given by:
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Parishram 2026
PHYSICS DPP: 1
Magnetism and Matter
(A) θ = 60º
(B) θ = 90º
(C) θ = 45º
(D) θ = 30º
(A) (B)
(C) M (D)
Answer Key
Q1 D Q6 B
Q2 D Q7 A
Q3 C Q8 A
Q4 B Q9 D
Q5 A
Q1 Text Solution:
Correct choice: D — pole strength q stays Initial :
the same, magnetic moment m becomes Final :
m/2.
Why (one-line proof):
Magnetic moment of a bar magnet is
where is the magnetic length.
Cutting perpendicular to the length leaves Video Solution:
the pole strength unchanged but halves the
length ( ), so each half gets
. NCERT’s worked Example 5.1
discusses this very division of a magnet .
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Q4 Text Solution:
Torque on a magnetic dipole:
(NCERT)
Q2 Text Solution:
For x ≫ d each magnet behaves like a point Video Solution:
dipole (moment m).
Axial field of dipole 1 at distance x:
.
Q5 Text Solution:
Hence , so .
Torque,
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Q3 Text Solution:
Work needed = increase in magnetic potential
energy
Q8 Text Solution:
(1)
Q6 Text Solution: [New NCERT Class 12th Page No. 139, 140]
Think of the two equal halves as dipoles of
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moment each.
After bending, the angle between their axes is
(each arm makes with the other), so
the resultant moment is
Q9 Text Solution:
(4)
Let m be strength of each pole of bar magnet
Hence the new magnet’s magnetic moment is of length l. Then M = m × l --- (i)
one-half of the original value. When the bar magnet is bent in the from of an
arc as shown in the figure
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Q7 Text Solution:
(1)
New magnetic dipole moment
M’ = m × 2r sin 30º
M = ml
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PARISHRAM 2026
PHYSICS
Assignment : 1
Moving Charges and Magnetism
velocity in a
magnetic field .
current. Now at any point A within the coil the Q12 A charge with and mass
magnetic field will be:
moving with a velocity of along x –
axis. A uniform static magnetic field of 0.5T is
acting along the y - axis. The mangetic force
(magnitude and direction) on charge:-
(A) Zero
(B) , along z-axis
(A) less than the magnetic field produced due (C) , along x - axis
to loop only. (D) , along y-axis
(B) more than the magnetic field produced due
Q13 An electron is moving along +x direction. To
to loop only.
get it moving along an anticlockwise circular
(C) equal to the earlier.
path in x-y plane, magnetic field applied along
(D) zero
:-
Q9 Current of 0.1 A circulates around a coil of 100 (A) + y – direction
turns and having radius equal to 5cm. The (B) + z – direction
magnetic field sets at the centre of the coil is (C) – y – direction
(A) (D) – z – direction
(B)
Q14 If cathode rays are projected at right angle to
(C)
magnetic field, their trajectory is
(D) (A) Ellipse
carrying same current is then ratio of Q15 A wire of length 5 cm. is placed inside the
solenoid near its centre such that it makes an
is:-
angle of 30º with the axis of solenoid. The wire
(A) 1 : 2 (B) 2 : 1
carries a current of 5A and the magnetic field
(C) 1 : 1 (D) 4 : 1
due to solenoid is 2.5 × T. Magnetic force
on the wire is :-
(A)
(B)
(D)
(C)
(D)
Q19 Two parallel wires are carrying electric
Q16 A wire 'LN' bent as shown in figure is placed in currents of equal magnitude and in the same
uniform perpendicular magnetic field of 5T. A direction. They exert
10A current flows through the wire. Magnetic (A) An attractive force on each other
force experienced by the wire is :- (B) A repulsive force on each other
(C) No force on each other
(D) A rotational torque on each other
(C) (D)
(D)
(A) A - Q B - P C - S, T D - Q
(B) A - Q B - P, R C - S, T D - Q
(C) A - Q B - P C - S, T D - R
(D) A - Q B - P C - S, T D - Q, R
(A) (B)
(C) (D)
Answer Key
Q1 D Q14 B
Q2 D Q15 B
Q3 D Q16 A
Q4 B Q17 A
Q5 B Q18 B
Q6 D Q19 A
Q7 A Q20 A
Q8 B Q21 D
Q9 A Q22 C
Q10 A Q23 A
Q11 D Q24 A
Q12 B Q25 C
Q13 B
Q1 Text Solution:
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Q4 Text Solution:
I = 2A
dl = 2cm = 0.02m
r = 4m
Q2 Text Solution:
or
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Q3 Text Solution:
According to Bio-Savart Law, the magnitude of
the magnetic field is
(i) directly proportional to the current through Q5 Text Solution:
the conductor i.e. dB I The magnetic field due to small element of
(ii) directly proportional to the length of the conductor of lenght is given by
current element i.e. dB dl
(iii) directly proportional sin
The value will be maximum when
(iv) inversely proportional to the square of the
sin = 1 sin 90° or = 90º
distance from the current element i.e. dB 1/
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Q9 Text Solution:
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Q7 Text Solution:
Q10 Text Solution:
Current and number of turns are equal for
both coils, so
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Q11 Text Solution:
Mangetic force on moving charge
Here:-
Q8 Text Solution:
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Q12 Text Solution:
Magnetic force on moving charge
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Q13 Text Solution:
In order to keep an electron moving along
anticlockwise circular path, it should
experience a centripetal magnetic force and at
this instant force should be along +y direction.
Now direction of external magnetic field can
be find out by right hand palm rule. Q16 Text Solution:
º º
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Hence .
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be .
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(D)
Bcentre = 0
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Force: .
Parishram 2026
DPP: 5
Physics
Moving Charges and Magnetism
(A)
(B)
(C)
(D)
Answer Key
Q1 C Q6 D
Q2 A Q7 A
Q3 C Q8 A
Q4 C Q9 C
Q5 C Q10 C
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Q2 Text Solution:
For a planar coil, magnetic dipole moment is
, where Video Solution:
= number of turns, = current, and
= area of one turn.
Hence .
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Q5 Text Solution:
Turning the wire of length into a single
circular loop gives
Q3 Text Solution:
The loop’s magnetic moment μ is
perpendicular to its plane. Magnetic moment of the loop:
Torque is τ = μ × B = μB sin θ, where θ is the
.
angle between μ and B.
Equilibrium requires τ = 0 ⇒ sin θ = 0 ⇒ θ = 0° Maximum torque in the uniform field occurs
or 180° (μ parallel or antiparallel to B). when the loop’s plane is parallel to :
Thus the plane—being perpendicular to μ—
must make 90° with the field direction.
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Q6 Text Solution:
Torque on a current loop is
Q8 Text Solution:
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Q7 Text Solution:
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Parishram 2026
Physics DPP: 4
(A)
Q2 A wire 'LN' bent as shown in figure is placed in
uniform perpendicular magnetic field of 5T. A
(B)
10A current flows through the wire. Magnetic
force experienced by the wire is :- (C)
(D)
Answer Key
Q1 B Q6 C
Q2 A Q7 C
Q3 A Q8 B
Q4 B Q9 A
Q5 A
Q1 Text Solution:
Magnetic field produced by solenoid along its
axis so magnetic force on conductor given as
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Q2 Text Solution:
º º
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Q3 Text Solution:
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Q6 Text Solution:
Since the force on the rod CD is non-uniform,
it will experience force and torque. From the Q9 Text Solution:
left hand side, it can be seen that the force will Force on 10cm length of wire AD :-
be upward and torque is clockwise.
...(i)
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...(ii)
Wire AB and DC located in non uniform
magnetic field
So force on elemental length of these wire will
be of same magnitude and opposite direction
therefore net force on wire AB and DC will be
Q7 Text Solution:
zero (always)
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PARISHRAM 2026
DPP: 3
PHYSICS
Moving Charges and Magnetism
(A) The two magnetic forces arc equal and some instant makes an acute angle with the
opposite, so they produce no net effect magnetic field. The path of the particle will be:
(B) The magnetic forces do no work on each (A) A straight line
particle (B) A circle
(C) The magnetic forces do equal and opposite (C) A helix with uniform pitch
(but non zero) work on each particle (D) A helix with non uniform pitch
(D) The magnetic forces are necessarily
Q10 In the given figure, the electron enters into the
negligible
magnetic field. It deflects in ...... direction:
Q8 When a charged particle enters a uniform
magnetic field?
(A) Speed of particle must increase
(B) Speed of particle must decrease
(C) Speed of particle will be constant
(D) Speed of particle may be decrease or (A) + ve X
increase (B) – ve X
(C) + ve Y
Q9 A charged particle moves in a uniform
(D) – ve Y
magnetic field. The velocity of the particle at
Answer Key
Q1 B Q6 B
Q2 B Q7 B
Q3 C Q8 C
Q4 A Q9 C
Q5 A Q10 D
Particle
Proton ( )
α-particle (
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)
Q3 Text Solution:
(The given speed ratio is irrelevant since
For motion perpendicular to a uniform -field,
depends only on .)
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Doubling doubles : .
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Q2 Text Solution:
Formula (uniform circular motion in -
field)
Q4 Text Solution:
For motion perpendicular to a uniform -field,
Hence
Given
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:
Force: .
is upward; is into the page.
Positive charges (p, α) deflect left.
Negative charge (e⁻) deflects right.
Only right-curving path is labelled D, Q7 Text Solution:
hence the electron follows D. The magnetic part of the Lorentz force
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Q6 Text Solution:
For a charged particle in uniform with
velocity ⟂ : Q8 Text Solution:
(C)
Since F is always perpendicular to velocity.
Hence speed remains constant.
[New NCERT Class 12th Page No. 138]
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Q9 Text Solution:
(3)
Conceptual question.
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Parishram 2026
DPP: 2
PHYSICS
Moving Charges and Magnetism
Q1 (C)
Rank the value of for the closed
paths shown in figure from the smallest to (D)
largest.
Q5 If a long hollow copper pipe carries a direct
current, the magnetic field associated with the
current will be
(A) Only inside the pipe
(B) Only outside the pipe
(C) Both outside and outside the pipe
(A) a,b,c,d (B) a,c,d,b
(D) Neither inside nor outside the pipe
(C) a,b,c,d (D) a,c,b,d
Q6 Field inside a solenoid is
Q2 A current of 1/(4 ) ampere is flowing in a long
(A) Directly proportional to its length
straight conductor. The line integral of
(B) Directly proportional to current
magnetic induction around a closed path (C) Inversely proportional to toal number of
enclosing the current carrying conductor is. turns
(A) weber per metre
(D) Inversely proportional to current
(B) weber per metre
(C) weber per metre Q7 The expression for magnetic induction inside a
(D) zero solenoid of length L carrying current I and
having N number of turns is
Q3 A solid cylindrical wire of radius 'R' carries a (A)
current 'I'. The ratio of magnetic fields at
(B)
points which are located at R/2 and 2R
(C)
distance away from the axis of the wire:-
(A) 1 : 1 (B) 1 : 2 (D)
(C) 2 : 1 (D) 1 : 4
Q8 There are 50 turns of a wire in every cm length
Q4 A hollow cylindrical wire carries a current I, of a long solenoid. If 4 ampere current is
having inner and outer radii R and 2R flowing in the solenoid, the approximate value
respectively. Magnetic field at a point which of magnetic field along its axis at an internal
3R/2 distance away from its axis is:- point and at one end will be respectively.
(A) (A)
(B) (B)
(C)
(D)
Answer Key
Q1 B Q6 B
Q2 A Q7 D
Q3 A Q8 C
Q4 C
Q5 B
Q1 Text Solution:
[Here, a = R, b =
2R, r 3R/2]
Q2 Text Solution:
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Q3 Text Solution:
Field inside the conductor:-
Q5 Text Solution:
....(1) According to Ampere's law
Field outside the conductor:-
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From (1) and (2)
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Q6 Text Solution:
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Q7 Text Solution:
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Q8 Text Solution:
The magnetic field in the solenoid along its
axis
(i) At an internal point
Parishram 2026
DPP: 1
PHYSICS
Moving Charges and Magnetism
Q1 Magnetic effect of current was discovered by (B) The magnitude of the magnetic field is
(A) Faraday (B) Oersted directly proportional to the length of the
(C) Ampere (D) Bohr current element.
(C) The magnetic of the magnetic field is
Q2 Magnetic field cannot be produced by
inversely proportional to the square of the
(A) Charge in uniform motion
distance from the current element.
(B) Charge at rest
(D) The magnetic of the magnetic field is
(C) Magnet
directly proportional to the square of the
(D) Current Carrying wire
distance from the current element.
Q3
The magnetic field to a small current Q6 Find the magnitude and direction of magnetic
field B, due to element of a wire lenght of 2cm
element at a distance and element having current of 2A in north direction at a
carrying current i is point 4m from the element along east.
(A) (A)
(B)
(B) (C)
(D)
(C)
Q7 For having maximum magnetic field due to a
small element of current carrying conductor at
(D)
a point, the angle between the element and
the line joining the element to the given point
must be
Q4 Unit of magnetic permeability is
(A) 0º (B) 90º
(A) Amp/metre
(C) 180º (D) 45º
(B) Amp/
(C) Henry Q8
(D) Henry/metre The magnetic field d in terms of the current
Q5 Which of the following is not correct about the density of a conducting wire is related as
Biot-Savart law? (A)
(A) The magnitude of the magnetic field is
directly proportional to the current through (B)
the conductor
(C)
(D)
(A) (B)
(C) (D)
Answer Key
Q1 B Q6 B
Q2 B Q7 B
Q3 D Q8 C
Q4 D Q9 D
Q5 D Q10 B
Q1 Text Solution:
Magnetic effect of current was discovered by
Oersted.
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Q5 Text Solution:
According to Bio-Savart Law, the magnitude of
the magnetic field is
(i) directly proportional to the current through
When a charged particle is at rest, it does not (ii) directly proportional to the length of the
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Q3 Text Solution:
Q4 Text Solution:
or
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Q7 Text Solution:
The magnetic field due to small element of
conductor of lenght is given by
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Q8 Text Solution:
We know tha current density Q10 Text Solution:
F = BIi
...(i)
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Q9 Text Solution:
By applying the Right Hand thumb rule, the
direction of the magnetic field would be
clockwise as shown in diagram around the
PARISHRAM 2026
PHYSICS DPP: 1
Electromagnetic Waves
Answer Key
Q1 A Q6 A
Q2 B Q7 C
Q3 B Q8 A
Q4 C Q9 D
Q5 C Q10 B
Video Solution:
Q5 Text Solution:
Displacement current has the same unit as
conduction current, which is Ampere (A).
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Q2 Text Solution:
Inside a long straight solenoid, the magnetic
field is uniform and parallel to the axis of the
solenoid
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Q6 Text Solution:
Displacement current Id = C = 2 × 10–12 X
1012 = 2 A.
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Q3 Text Solution:
Inside the wire (r < a), the magnetic field
increases linearly with distance r from the
center, given by
B=
Q7 Text Solution:
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• Ampere’s Circuital Law states that the line
integral of the magnetic field around any
closed path is equal to the permeability of free
space times the total current enclosed by the
path.
• The law is mathematically expressed as
, where is the line
Q4 Text Solution:
integral of the magnetic field B around a
James Clerk Maxwell introduced the concept of
closed loop, μ0 is the permeability of free
displacement current to modify Ampère's Law,
PARISHRAM 2026
PHYSICS Assignment : 1
Alternating Current
across the primary, the voltage developed in (C) Assertion is true but Reason is false.
the secondary would be: (D) Both Assertion and Reason are false.
Q4 Match column I with column II, and choose the of mutual induction.
correct combination from the options given (A) Both Assertion and Reason are true and
Answer Key
Q1 B Q6 B
Q2 D Q7 B
Q3 D Q8 D
Q4 B Q9 A
Q5 C Q10 A
Q1 Text Solution:
(R)
(B) RMS current of constant current of
2.8 A = RMS of DC = 2.8 A → (P)
Q2 Text Solution: (C) Transformers work only in AC
circuits → (Q)
Ps = 60 W (given for the lamp).
(D) Capacitors act as infinite resistance
Pp = Ps = 60 W. in DC circuits → (S)
Vp = 220 V (primary voltage).
Matching:
Pp = Vp * Ip 60 = 220 * Ip.
Ip = 60 / 220 = 6 / 22 = 3 / 11 A ≈ 0.27 A. A–R
B–P
(NEW NCERT 12th Page No. 194) C–Q
D–S
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Q3 Text Solution:
A step-up transformer requires alternating Q5 Text Solution:
current (AC) to function. A Leclanché cell Assertion is true:
provides direct current (DC). Electrical power is transmitted at high voltage
Transformers do not work with DC — there’s to reduce power loss during transmission.
no changing magnetic flux, so no EMF is Reason is false:
induced in the secondary. At high voltage, for same power , the
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Q6 Text Solution:
Assertion is true:
In a practical transformer, some power is Q9 Text Solution:
lost due to heat, eddy currents, hysteresis, Given (ideal transformer):
etc., so output < input.
Reason is true: Primary voltage , current
A transformer does work on the principle of
mutual induction. Secondary voltage
But — mutual induction is not the reason
In an ideal transformer:
for power loss; it's just the working principle.
Video Solution:
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Q7 Text Solution:
In a step-up transformer, the secondary
voltage is greater than the primary voltage.
So:
Q10 Text Solution:
AC is transmitted at high voltage to minimize
current for a given power . Lower
current reduces power loss due to resistance
Video Solution:
in transmission lines, since power loss .
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Q8 Text Solution:
The core of a transformer is laminated to:
PARISHRAM 2026
PHYSICS DPP: 2
Alternating Current
Q1 Match List-I with List-II (D) Voltage leads the current by 60º
List-I List-II
Q4 For a series RLC circuit R = = . The
impedance of the circuit and phase difference
Purely capacitive
A I. between V and i will be
circuit
(A)
Q3 Voltage and current in an ac circuit are given Q7 The reading of the A.C. voltmeter in the
by and network shown in figure is (where V is in volt)
(C) (D)
Answer Key
Q1 C Q6 C
Q2 C Q7 C
Q3 C Q8 C
Q4 B Q9 C
Q5 B Q10 B
Q1 Text Solution:
(3)
In purely capacitive, current leads voltage by
90° In purely inductive, current lags voltage by
90°
At resonance, XC = XL
i.e., Z = R Q4 Text Solution:
(2)
Video Solution:
Also
Q2 Text Solution:
(3)
As dielectric is placed, capacitance will [New NCERT Class 12th Page No. 186-189]
increase.
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Q5 Text Solution:
(2)
Resonance frequency
rad/sec
Resonance current =
Q3 Text Solution:
(3) Video Solution:
Current leading the voltage by 60°.
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Q6 Text Solution:
(3)
For series R-L-C circuit,
Q9 Text Solution:
rad/s
[New NCERT Class 12th Page No. 187] Using phasor analysis,
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Q7 Text Solution:
(3)
At resonance
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PARISHRAM 2026
PHYSICS DPP: 1
Alternating Current
Q1 The peak value of an alternating e.m.f. which is reaching from zero to maximum value and the
given by E = cos is 10 volts and its peak value of current will be
Q3 The peak value of 220 volts of ac mains is Q8 The maximum value of a.c. voltage in a circuit
(A) 155.6 volts is 707V. Its rms value is approximately:-
(B) 220.0 volts (A) 70.7V (B) 100V
(C) 311.0 volts (C) 500V (D) 707V
(D) 440 volts
Q9 The r.m.s. voltage of domestic electricity
Q4 If an A.C. main supply is given to be 220 V. supply is 220 volt. Electrical appliances should
What would be the average e.m.f. during a be designed to withstand an instantaneous
positive half cycle:- voltage of
(A) 198 V (A) 220V (B) 310V
(B) 386 V (C) 330V (D) 440V
(C) 256 V
(D) None of these Q10 Assertion (A): The average value of alternating
current over a complete cycle is zero.
Q5 If represents the peak value of the voltage Reason (R): In a complete cycle, the positive
in an ac circuit, the r.m.s. value of the voltage and negative halves of the current cancel each
will be other.
(A) (B) (A) Both A and R are true and R is the correct
explanation of A.
(C) (D)
(B) Both A and R are true but R is not the
correct explanation of A.
Q6 The r.m.s. value of an ac of 50Hz is 10 amp.
(C) A is true but R is false.
The time taken by the alternating current in
(D) A is false but R is true.
Answer Key
Q1 B Q6 D
Q2 C Q7 B
Q3 C Q8 C
Q4 A Q9 B
Q5 D Q10 A
Vavg=π2×311≈3.1416622≈. 198V
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Q2 Text Solution:
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Q3 Text Solution:
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Q7 Text Solution:
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Q8 Text Solution:
Q10 Text Solution:
The alternating current reverses its direction
Video Solution: periodically. Over one complete cycle, the area
under the curve above the time axis is equal
and opposite to the area below the axis.
Hence, their average value is zero.
The reason correctly explains this cancellation.
Video Solution:
Q9 Text Solution:
PARISHRAM 2026
PHYSICS DPP: 3
Electromagnetic Induction
Q1 Consider a pair of coils arranged coaxially solenoid is 4 H, then the mutual inductance
parallel to each other, in a vertical plane. When of the solenoid due to solenoid will be:
the current in one coil increases from 0 to 10 A (A) 4 H (B) 8 H
in 0.5 s, the emf induced in the other coil is 20 (C) 2 H (D) None of these
V. The mutual inductance of the coil is:
(A) 4.0 H (B) 0.5 H Q5 The mutual inductance between a pair of a
(C) 2.0 H (D) 1.0 H coils A and B placed close to each other
depends upon
Q2 The maximum possible mutual inductance (A) the rate of change of current in A
between the two coils of self inductance (B) the rate of change of current in A and B
is (C) the material of the wire of the coils
(A) (B) (D) the relative position and orientation of A
and B
(C) (D)
Q6 A 100 turn coil of area 0.1 m2 rotates at half a
Q3 Consider two coaxial cylinder of same Length revolution per second. It is placed in a uniform
L, with vaccum inside them. The radii of the magnetic field of 0.01 T perpendicular to the
inner solenoid and the outer solenoid are axis of rotation of the coil. Calculate the
respectively. The number maximum voltage generated in the coil?
of turns per unit length are for the (A) 256.33 V (B) 89.12V
inner solenoid and the outer solenoid, (C) 0.314 V (D) 3.1455 V
respectively. The mutual inductance is:
Q7 Name the current induced in solid metallic
(A)
masses when the magnetic flux threading
(B) through them changes.
(C) (A) Ampere currents
(D) (B) Faraday currents
(C) Eddy currents
Q4 Two long solenoids have equal (D) Solenoidal currents
lengths and the solenoid is placed co-axially
Q8 An a.c. generator consists of a coil of 50 turns
inside the solenoid . The ratio of the radius
and an area 2.5 m2 rotating at an angular
of the solenoid is 1 : 2. If the
speed of 60 rad s–1 in a uniform magnetic field
mutual inductance of the solenoid due to
of 0.3 T between two fixed pole pieces. What is
the flux through the coil, when the current is Q10 Assertion: The mutual inductance between
zero? two coils is maximum when the coils are
(A) Maximum wound on each other.
(B) Minimum Reason: The flux linkage between two coils is
(C) Zero maximum when they are wound on each
(D) Independent of current other.
(A) Both Assertion and Reason are true and
Q9 An a.c. generator consists of a coil of 1000
Reason is the correct explanation of the
turns and cross sectional area of 3m2, rotating Assertion .
at a constant angular speed of 60 rad s–1 in a (B) Both Assertion and Reason are true, but
uniform magnetic field 0.04 T. The resistance Reason is not the correct explanation of the
of the coil is 500Ω. Calculate the maximum Assertion .
current drawn from the generator. (C) Assertion is true, but Reason is false.
(A) 2500 A (B) 14.4 A (D) Assertion is false and Reason is also false.
(C) 6.25 A (D) 0.55 A
Answer Key
Q1 D Q6 C
Q2 A Q7 C
Q3 B Q8 A
Q4 A Q9 B
Q5 D Q10 A
Q2 Text Solution:
Self-induction:
1. Self - induction is the property of the current
carrying coil that resists or opposses the
change of current flowing through it.
2. This occurs mainly due to the self induced Hence, option A is correct.
emf producecd in the coil itself. Video Solution:
Q4 Text Solution:
Mutual - inductance
the current and voltage in a secondary coil is Mutual inductance for two co-axial solenoids:
mutual inductance
Let two long solenoids of
The mutual inductance, equal length are placed co-axially as
Explanation: shown in the figure.
Lets conside L is the length of the coaxial
The solenoid is placed inside the
cylinder.
solenoid .
are the numbers of turns of the
The mutual inductance of both the
inner solenoid and the outer solenoid
solenoids will be equal and it is given as,
respectively.
The mutual inductance is .
For medium of relative permeability
Video Solution:
Video Solution:
Q6 Text Solution:
The maximum voltage generated in the coil,
e0 = nBAω
e0 = nBA × (2πv)
e0= 100 × 0.01 × 0.1 × 2π × 0.5
e0 = 0.314 V Q9 Text Solution:
e0 = nBAω
Video Solution:
e0 = 1000 × 0.04 × 3 × 60 e0 = 7200 V.
Video Solution:
Q7 Text Solution:
Eddy currents are the currents induced in solid
metallic masses when the magnetic flux
threading through them changes. These
currents look like eddies or whirlpools in water Q10 Text Solution:
and so they are known as eddy currents. Both Assertion and Reason are true and
Video Solution: Reason is the correct explanation of the
Assertion.
Video Solution:
Q8 Text Solution:
The current is zero when the coil is vertical. In
this position, flux through the coil is maximum.
PARISHRAM 2026
Physics DPP: 2
Electromagnetic Induction
depends upon
(A) the rate of change of current in A
(B) the rate of change of current in A and B
(C) the material of the wire of the coils
(D) the relative position and orientation of A
and B
Answer Key
Q1 A Q6 D
Q2 B Q7 D
Q3 D Q8 B
Q4 B Q9 B
Q5 D
Q1 Text Solution:
Video Solution:
Q4 Text Solution:
Video Solution:
Q2 Text Solution:
volt
l = effective length
Video Solution:
Video Solution:
Q3 Text Solution:
Q5 Text Solution:
Energy stored in inductor coil is given by
B = constant
A = l2 = constant
Video Solution:
Calculation:
Rate of change of current in A (Incorrect):
Given that N = 200 turns; i = 2A; = 4mWb = 4 Mutual inductance is a geometric
× 10–3 Wb; property and does not depend on how
fast the current changes.
Rate of change of current in A and B
(Incorrect): While emf depends on the
L = 0.4 H rate of change of current, mutual
So the correct answer is option D. inductance does not.
Video Solution: Material of the wire (Incorrect): The
material of the wire does not significantly
affect mutual inductance.
Relative position and orientation of coils
(Correct Answer): The distance and
alignment of the coils directly influence
their mutual inductance.
Q7 Text Solution:
The mutual inductance between A and B
Mutual inductance (M) between two coils depends on the relative position and
quantifies the ability of one coil to induce orientaton of A and B.
an electromotive force (emf) in the other Video Solution:
due to a changing current.
It depends on the geometric
arrangement of the coils, not on the rate
of change of current.
Video Solution:
Q8 Text Solution:
Mutual Inductance: Q9 Text Solution:
when two coils are brought in proximity to When two coils are arranged in such a way
each other the magnetic field in one of the that a change of current in one coil causes an
coils tends to link with the other. emf to be induced in the other, the coils are
said to have mutual inductance.
The mutual inductance is denoted letter M and
measured in Henry.
Induced emf in coil A due to the change in
current in coil B is
Where, di = change in current , dt = change in
time, M = mutual inductance
calculation:
Given,
Explanation:
Lets conside L is the length of the coaxial
cylinder.
are the numbers of turns of the
inner solenoid and the outer solenoid
respectively.
The mutual inductance is .
PARISHRAM 2026
PHYSICS DPP: 1
Electromagnetic Induction
Q1 We have a coil as shown in the figure. Firstly Q3 In the given figure when the tapping key K is
the north pole of a bar magnet is moved pressed:
towards the coil on the left side and then the
south pole of the bar magnet is moved away
from the coil on the right side, then the
direction of the deflection in the galvanometer
will be:
(D) Faraday's law and conservation of charge T, where is constant.The magnitude of flux
passing through the saqure is:
Q6 A bar magnet is dropped and it passes
(A) (B)
through a copper ring as shown in the
(C) (D)
diagram. The acceleration of the falling
magnet while passing through the ring is
Answer Key
Q1 B Q6 C
Q2 B Q7 C
Q3 B Q8 A
Q4 D Q9 D
Q5 A Q10 C
Video Solution:
Q5 Text Solution:
Faraday's Laws of Electromagnetic Induction: coil produces electric energy within the
coil.
Whenever the number of magnetic lines of
force (magnetic flux) passing through a This phenomenon can be best explained
circuit called induced emf. The induced emf is Lenz's law depends on the principle of
given by the rate of change of magnetic flux conservation of energy and Newton's
Video Solution:
Lenz law:
Explanation:
Q8 Text Solution:
As the magnet falls the flux through the
Magnetic flux is given by the formula:
ring changes.
Regardless of whether the flux increases
Where :
or decreases, by Lenz's law a current is
induced in the ring that opposes the – is the magnetic flux.
change in flux. – B is the magnetic field induction (in Wb/ ).
This induced current induced a magnetic – A is the area of the surface
field that interacts with the falling – is the angle between the magnetic field and
magnet and decreases the acceleration the normal (perpendicular) to the surface.
of fall below g. Hence, the acceleration of The area A of a circular disc is given by the
the falling magnet while passing through formula:
the ring is less than the acceleration due
to gravity. Where r is the radius of the disc. Given r =
0.2m:
Video Solution:
The magnetic flux linked with the disc is: Since the net magnetic flux through any closed
surface is zero. We conclude that:
Net magnetic flux = 0
Video Solution: The net magnetic flux through any closed
surface is zero.
Video Solution:
Q9 Text Solution:
To solve the question regarding the net
magnetic flux through any closed surface, we Q10 Text Solution:
can follow these steps: The magnetic flux linked with uniform surface
Magnetic flux through a surface is defined of area of A in uniform magnetic field given by
as the integral of the magnetic field (B) over
that surface. Mathematically, it is expressed
as:
PARISHRAM 2026
PHYSICS Assignment : 1
Current Electricity
(C)
(D) (A) 5 A
(B) 3 A
(C) –3A
(D) –5/6 A
(C) (D)
Q13 n identical cell each of emf and internal Q16 A high-voltage transmission line has an
resistance r, are joined in series to from a aluminium cable of diameter 3.0 cm, 200 km
closed circuit. The potential difference across long. The resistivity is . The
any one cell is- resistance of this cable is;
(A) Zero (A) (B)
(B) (C) (D)
(C)
(D) Q17 Two copper wires have their masses in the
ratio 2 : 3 and the lengths in the ratio 3 : 4, The
Q14 Three 60 W, 120 V light bulbs are connected ratio of their resistances is;
across a 120V power source. If resistance of (A) 4 : 9 (B) 27 : 32
each bulb does not change with current, the (C) 16 : 9 (D) 27 : 128
find out total power delivered to the three
Q18 Statement I : A uniform wire of resistance 80
bulbs.
is cut into four equal parts. These parts are
now connected in parallel. The equivalent
resistance of the combination will be 5 .
Statement II : Two resistance 2R and 3R are
connected in parallel in a electric circuit. The
value of thermal energy developed in 3R and
(A) 180 W (B) 20 W 2R will be in the ratio 3 : 2.
(C) 40 W (D) 60 W Among the above given statements, choose
the most appropriate answer from the options
Q15 Consider the following statements regarding
given below:
the network shown in the figure :
(A) Both statement I and statement II are
correct
(B) Both statement I and statement II are
incorrect
(C) Statement I is correct but statement II is
incorrect
(D) Statement I is incorrect but statement II is
correct.
1. The equivalent resistance of the network
between points A and B is independent of Q19 The charge flowing through a resistance
value of G.
varies with time as , where
2. The equivalent resistance of the network
and are positive constants. The total heat
between points A and B is
produced in is
3. The current through G is zero.
(A) (B)
Which of the above statements is/are true?
(A) (1) alone (C) (D)
(B) (2) alone
Answer Key
Q1 C Q10 C
Q2 B Q11 A
Q3 C Q12 D
Q4 D Q13 A
Q5 C Q14 C
Q6 A Q15 D
Q7 D Q16 C
Q8 B Q17 B
Q9 D Q18 C
Q19 A
Video Solution:
Q2 Text Solution:
Video Solution:
Q3 Text Solution:
Q5 Text Solution:
Ohm's Law is not obeyed by semiconductors.
Temperature dependence of resistivity for a
Video Solution: typical semiconductor.
Video Solution:
Video Solution:
Q9 Text Solution:
Q7 Text Solution: Suppose current through different paths of
the circuit is as follows.
Hence,
Video Solution:
Q8 Text Solution:
2A and
current in each branch = 1A
Q10 Text Solution:
Video Solution:
Video Solution:
Video Solution:
Video Solution:
Upper:
Lower:
Q17 Text Solution:
These two paths are in parallel, so:
Given:
Mass ratio:
Energy in :
So,
Video Solution:
Ratio:
Original resistance =
Cut into 4 equal parts ⇒ each part =
Connected in parallel:
Q19 Text Solution:
We are given:
✅ Statement I is correct
Current is:
Statement II:
Expand:
Video Solution:
Now evaluate from to :
Plug in :
PARISHRAM 2026
DPP: 4
PHYSICS
Current Electricity
Answer Key
Q1 A Q6 C
Q2 A Q7 B
Q3 C Q8 (2)
Q4 C Q9 A
Q5 A Q10 B
Q1 Text Solution:
(A)
Given:
Power rating
Time
Cost per kWh = Rs. 2 Q3 Text Solution:
Given:
Energy consumed:
Power rating at
Q2 Text Solution:
Given (Case 1):
Energy produced in 600 s:
Energy
Time
Current
Video Solution:
Using:
, Q4 Text Solution:
Given: Three identical resistors A, B, and C,
where B and C are in parallel, and this
combination is in series with A.
Video Solution: Let each resistance be , and total voltage
supplied be .
Total resistance:
Step 1: Resistance of the bulb
Heat in A:
Video Solution:
Clearly:
Video Solution:
Q6 Text Solution:
Given:
Q5 Text Solution:
Given:
Q8 Text Solution:
The resistor is cut into equal parts:
Calculate the current for the light bulb using its
each part has resistance
power rating:
Step 2
Calculate the resistance for the light bulb:
All parts are connected in parallel.
Video Solution:
Step 2: New power dissipation:
Video Solution:
Q9 Text Solution:
(1)
In series
In parallel
Video Solution:
Q7 Text Solution:
(2)
Video Solution:
PARISHRAM 2026
DPP: 3
PHYSICS
Current Electricity
(A) DE (B) CD
(C) BC (D) AB
current through the side is it. If the current increases to 3A, the energy
developed in 10 s is;
(A) 450 J (B) 410 J
(C) 540 J (D) 45 J
consumed?
(A) 50 W (B) 75 W
(C) 100 W (D) 25 W
Answer Key
Q1 B Q11 A
Q2 B Q12 A
Q3 A Q13 A
Q4 D Q14 D
Q5 A Q15 C
Q6 D Q16 A
Q7 B Q17 A
Q8 B Q18 C
Q9 A Q19 B,D
Q10 A Q20 A
Q1 Text Solution:
Given:
Given:
Current
First 5 parts in series: Voltage across resistor
Q4 Text Solution:
Final combination (series of and
): Step-by-step solution:
Video Solution:
Video Solution:
Q5 Text Solution:
At , terminal voltage
Video Solution:
Q6 Text Solution:
Given:
Video Solution:
Video Solution:
Q8 Text Solution:
Assertion (A):
Q9 Text Solution:
"In the circuit shown, if
"
EMF of battery = 4 V
Resistor
Current
Video Solution:
This is the voltage drop across the resistor,
and direction of current matches the
polarity of battery.
So,
Gain =
3. D → E:
Battery , going from + to –
Drop =
4. E → B:
Current through resistor
Q12 Text Solution:
Drop =
(A)
Given:
Total sum of voltages:
Power rating
Time
Cost per kWh = Rs. 2
Video Solution:
Energy consumed:
Total cost:
Total resistance
Current
Current Energy
Time
Current
Ratio of currents:
Using:
Power dissipated:
Video Solution:
Given , so:
Operating voltage
🔹 Step 5: Direction
Step 4: Value of series resistance
Since net EMF is from A to B via E (10 V
dominates),
👉 Current flows from A to B through E
Video Solution:
Explanation: Net EMF is 5 V, total resistance is
10 Ω, giving 0.5 A in the direction of the
stronger battery (10 V).
Video Solution:
Bulb rating:
Mains supply: Step:
Bulb works perfectly when resistance
From point A to C:
is added in series.
Voltage drop across 2 Ω =
Battery = 2 V (drop)
Step 1: Resistance of the bulb
→
Assume
Then,
Video Solution:
PARISHRAM 2026
DPP: 2
PHYSICS
Current Electricity
Q1 The resistance of a wire (its temperature Q5 Which of the following graphs represents the
coefficient ) is at . If its variation of resistivity ( ) with temperature (T)
temperature is increased twice the initial for copper
value, the final resistance of the wire is; (A)
(A) (B)
(C) (D)
(B) 3 : 2 : 1
(C) 6 : 3 : 2
(D) 2 : 3 : 6
(A) 1 : 2 : 3
Answer Key
Q1 D Q6 A
Q2 C Q7 D
Q3 B Q8 B
Q4 B Q9 B
Q5 B Q10 C
So,
Video Solution:
Q2 Text Solution:
Given:
Diameter
Length
Resistivity
Q4 Text Solution:
Mass ratio:
Length ratio:
Video Solution:
So,
Video Solution:
Q3 Text Solution:
Video Solution:
Video Solution:
Q6 Text Solution:
Given:
Step 5: Calculate a
Video Solution:
Q9 Text Solution:
On increasing temperature of wire the kinetic
energy of free electrons increase and so they Video Solution:
Video Solution:
PARISHRAM 2026
DPP: 1
PHYSICS
Current Electricity
Q1 10,000 alpha particles pass per minute section of the conductor during t = 2s to t = 3s
through a straight tube of radius r. What is the is :-
resulting electric current? (A) 10 C (B) 24 C
(A) (C) 33 C (D) 44 C
(B)
Q6 In a Neon discharge tube
(C)
(D) ions move to the right each second, while
electrons move to the left per
Q2 The current through a wire depends on time
second; electron charge is . The
as i = (2 + 3t) A. Calculate the charge crossed
current in the discharge tube is :-
through a cross section of the wire in first 10
(A) 1 A towards right
seconds.
(B) 0.66 A towards right
(A) 150 C (B) 165 C
(C) 0.66 A towards left
(C) 170 C (D) 175 C
(D) zero
Q3 When no current flows through a conductor
Q7 The plot represents the flow of current
(A) the free electrons do not move
through a wire for different time intervals. The
(B) the average speed of a free electron over a
ratio of charges flowing through the wire
large period of time is zero.
corresponding to these time intervals is (see
(C) the average velocity of a free electron over
figure) :-
a large period of time is zero.
(D) the average of square of velocities of all the
free electrons at an instant is zero.
In the light of the above statements, choose Q9 Statement I: There is no current in the metals
the correct answer from the options given in the absence of electric field.
below: Statement II: Motion of free electrons is
(A) Both A and R are true but R is NOT the random.
correct explanation of A. (A) If both statements are true and statement
(B) Both A and R are true and R is the correct II is the correct explanation of statement I.
explanation of A. (B) If both statements are true but statement II
(C) A is false but R is true. is not the correct explanation of statement
(D) A is true but R is false. I.
(C) If statement I is true but statement II is
false.
2
(D) If both statements are false.
Answer Key
Q1 C Q6 B
Q2 C Q7 C
Q3 C Q8 B
Q4 D Q9 A
Q5 B
Charge of electron
Equivalent current:
Video Solution:
Video Solution:
Q2 Text Solution:
Q5 Text Solution:
Video Solution:
Video Solution:
Q3 Text Solution:
Due to random motion net velocity of all the
free e– is zero, so no current flows through the
Q6 Text Solution:
conductor at room temperature.
i = 4.1 × 1018 × 1.6 × 10–19
Video Solution:
= 0.66 A towards right
Video Solution:
Q4 Text Solution:
Q7 Text Solution:
Video Solution:
Q9 Text Solution:
Q8 Text Solution:
"There is no current in the metals in the absence
True – In absence of an electric field, the net
of electric field."
current is zero in metals because there's no
Without an electric field, free electrons move
directed movement of electrons.
randomly, so net current = 0
True – The free electrons in metals move
randomly when no external field is applied, so "Motion of free electrons is random."
their net motion cancels out. Even without a field, electrons move randomly
The random motion of electrons explains due to thermal energy
why net current is zero without an electric
field. The random motion of electrons results in no
net flow, hence no current.
Video Solution:
So, Statement II is the correct explanation
of Statement I.
Video Solution:
PARISHRAM 2026
PHYSICS ASSIGNMENT: 1
Q1 The electric potential inside a conducting Q5 Which of the following about potential
sphere difference between any two points is true?
(A) increases from centre to surface I. It depends only on the initial and final
(B) decreases from centre to surface position.
(C) remains constant from centre to surface II. It is the work done per unit positive charge
(D) is zero at every point inside in moving from one point to other.
III. It is more for a positive charge of two units
Q2 Which of the following about potential at a
as compared to a positive charge of one unit.
point due to a given point charge is true?
(A) I only (B) II only
The potential at a point P due to a given point
(C) I and II (D) I, II and III
charge
(A) is a function of distance from the point Q6 Consider the following statements and select
charge. the correct option
(B) varies inversely as the square of distance I. In an external electric field, the positive and
from the point charge. negative charges of a non-polar molecule are
(C) is a vector quantity displaced in opposite directions.
(D) is directly proportional to the square of II. In non -polar molecules displacement stops
distance from the point charge. when the external force on the constituent
charges of the molecule is balanced by the
Q3 To obtain capacity from three capacitors
restoring force.
of each, they will be arranged. III. The non-polar molecule develops an
(A) all the three in series induced dipole moment.
(B) all the three in parallel (A) I and II (B) II and III
(C) two capacitors in series and the third in (C) I and III (D) I, II and III
parallel with the combinatioin of first two
(D) two capacitors in parallel and the third in Q7 In which of the following cases is the electric
series with the combination of first two field zero but potential is not zero at a point on
-axis ?
Q4 The work done in placing a charge of (A)
coulomb on a condenser of
capacity 100 micro-farad is
(A) joule
(B) joule
(C) joule
(D) joule
(B)
(C)
(A) changes, V remains unchanged
(C)
assertion
(C) Assertion is correct, reason is incorrect
(D) Assertion is incorrect, reason is correct.
Q16 An electric charge is placed at the disconnected from it. A dielectric slab of
origin (0,0) of co-ordinate system. Two dielectric constant K, which can just fill the air
gap of the capacitor, is now inserted in it.
points A and B are situated at and
Which of the following is incorrect?
(2,0) respectively. The potential difference
(A) The energy stored in the capacitor
between the points A and B will be
decreases K times.
(A) 4.5 volt (B) 9 volt
(B) The chance in energy
(C) zero (D) 2 volt
stored is
Q17 The expression (C) The charge on the capacitor is not
implies, that electric
conserved.
field is in that direction in which
(D) The potential difference between the plates
(A) increase in potential is steepest.
decreases K times.
(B) decrease in potential is steepest.
(C) change in potential is minimum.
(D) None of these
(A) increase
(B) decrease
(C) remain unchanged
(D) become zero
Answer Key
Q1 C Q11 B
Q2 A Q12 D
Q3 C Q13 A
Q4 C Q14 C
Q5 C Q15 D
Q6 D Q16 C
Q7 C Q17 B
Q8 D Q18 A
Q9 A Q19 C
Q10 C Q20 C
Q1 Text Solution:
Electric potential inside a conductor is
constant and it is equal to that on the surface
of the conductor.
Video Solution:
Q5 Text Solution:
Since , more work will be done for a
positive charge of two units as compared to
positive charge of one unit, but the ratio is
same. Therefore potential difference is same.
Q2 Text Solution:
Video Solution:
Since , for a given point charge, q
is constant, therefore V depends only on r .
Hence V is a function of distance.
Video Solution:
Q6 Text Solution:
In an external electric field, the positive and
negative charges of a non-polar molecule are
displaced in opposite directions. The
Q3 Text Solution: displacement stops when the external force on
the constituent charges of the molecule is
balanced by the restoring force (due to
Video Solution:
internal fields in the molecule). The non-polar
molecule thus develops an induced dipole
moment. The dielectric is said to be polarised
by the external field.
Video Solution:
Q4 Text Solution:
Work done
Video Solution:
Q7 Text Solution:
In this case electric fields due to the two
charges at origin are just equal and opposite
Video Solution:
Video Solution:
Q8 Text Solution:
The potential energy of a dipole in uniform
electric field is given by
Video Solution:
Video Solution:
Q9 Text Solution:
As shown in the figure, the resultant electric
Q11 Text Solution:
fields before and after interchanging the
If V is the potential applied across the
charges will have the same magnitude, but
capacitor then p.d. across each capacitor will
opposite directions.
be . When
Also, the potential will be same in both cases
as it is a scalar quantity.S A-1: dielectric is inserted in capacitor B, then
B-1:
C-2 : and
D-2 : On solving above equations, we get
charges:
Video Solution:
Q13 Text Solution:
Assertion is correct, reason is correct; reason
is a correct explanation for assertion.
Video Solution:
Equivalent circuit
b:a
Video Solution:
C1 and C2 are in series, also C3 and C4 are in
series.
Hence
and B is given by
W.d. by battery
Video Solution:
Now, potential at
Q19 Text Solution:
remain unchanged
Potential difference between the points A
Video Solution:
Q1 A capacitor has a capacitance of 50 pF , which (D) depends on the nature of the material
increases to 175 pF with a dielectric material inserted
between its plates. What is the dielectric
Q5 Can a metal be used as a medium for
constant of the material?
dielectric?
(A) 2.5 (B) 3.5
(A) Yes
(C) 4.5 (D) 5.5
(B) No
Q2 The capacity and the energy stored in a (C) Depends on its shape
parallel plate condenser with air between its (D) Depends on dielectric
plates are respectively C0 and W0. If the air
Q6 Assertion (A): Inserting a dielectric into a
between the plates is replaced by glass
charged capacitor connected to a battery
(dielectric constant = 5) find the capacitance of
increases the stored energy.
the condenser and the energy stored in it.
Reason (R): Capacitance increases and voltage
(A) (B)
remains constant, so energy increases.
(C) (D) (A) Both A and R are true, and R is the correct
explanation of A.
Q3 A parallel plate capacitor is to be designed (B) Both A and R are true, but R is not the
with a voltage rating 1 kV using a material of correct explanation of A.
dielectric constant 10 and dielectric strength (C) A is true but R is false.
Q2 C Q7 D
Q3 A Q8 A
Q4 C Q9 A
Q5 B Q10 A
Video Solution:
Video Solution:
Q5 Text Solution:
No
Video Solution:
Q6 Text Solution:
Both A and R are true, and R is the correct
explanation of A.
Q3 Text Solution:
Video Solution:
Video Solution:
Q7 Text Solution:
Q4 Text Solution:
Q = CV; Video Solution:
when a slab of dielectric medium is placed
capacitance is increased so charge is
Video Solution:
Video Solution:
Q9 Text Solution:
(A)
(B)
PARISHRAM 2026
DPP: 6
PHYSICS
Electrostatic Potential and Capacitance
(A) 8 mF (B) 6 mF
(C) (D)
(A)
Q2 In an adjoining figure three capacitors C1, C2 (B)
(C)
and C3 are joined to a battery. The correct
(D)
condition will be : (Symbols have their usual
meanings) Q5 The effective capacitance between the points P
and Q of the arrangement shown in the figure
is :
(A)
(B) (A)
(C) (B)
(D) (C)
(D)
Q3 A number of capacitors, each of capacitance 1
and each one of which gets punctured if a Q6 Two capacitors of capacity C1 and C2 are
(C)
(D)
(A)
(B)
(C)
(D)
(C) (D)
Answer Key
Q1 C Q6 C
Q2 C Q7 A
Q3 C Q8 B
Q4 A Q9 C
Q5 B Q10 B
Q1 Text Solution:
Video Solution:
total capacitors
Video Solution:
Q2 Text Solution:
V2 = V3 {Because C2 and C3 in parallel}
Q1 = Q2 + Q3
Q4 Text Solution:
V = V1 + V2
Given circuit is balanced wheat stone bridge.
Hence effective capacity is
Video Solution: Video Solution:
Q6 Text Solution:
Common potential
Charge on
Video Solution:
Charge on
Video Solution:
Q9 Text Solution:
As the potential of two spheres is same hence
there will be no flow of charge.
Video Solution:
Q7 Text Solution:
Charge on plate
Charge on plate
Video Solution:
Video Solution:
Q8 Text Solution:
Let Initial charge = q
then from charge conservation
Q1 A capacitor of capacitance C has a charge Q. volt. Calculate the charge spent for
The net charge on the capacitor is always each flash.
(A) zero (B) infinite (A) 0.07 C (B) 0.09 C
(C) positive (D) Negative (C) 0.08 C (D) 0.06 C
Q2 A capacitor gets a charge of when it is Q6 Two capacitors C1 and C2 have equal amount
connected to a battery of emf 5 V . Calculate
of energy stored in them. What is the ratio of
the capacity of the capacitor.
potential differences across their plates?
(A)
(A)
(B)
(C) (B)
(D)
(C)
Q3 When 2 × 1016 electrons are transferred from
(D)
one conductor to another, a potential
difference of 10 V appears between the
Q7 To increase the charge on the plate of a
conductors. Calculate the capacitance of the
capacitor implies to :-
two conductors system.
(A) decrease the potential difference between
(A)
the plates.
(B)
(B) decrease the capacitance of the capacitor.
(C)
(C) increase the capacitance of the capacitor.
(D)
(D) increase the potential difference between
Q4 The graph shows the variation of voltage V the plates.
across the plates of two capacitors A & B with
Q8 Capacitors are used in electrical circuits where
charge Q . Which of the two capacitors has
appliances need rapid :
larger capacitance?
(A) Current (B) Voltage
(C) Watt (D) Resistance
Q2 B Q7 D
Q3 D Q8 A
Q4 C Q9 A
Q5 B Q10 B
Q1 Text Solution:
Zero
Video Solution:
Q5 Text Solution:
Q = CV = 0.09 C
Video Solution:
Q2 Text Solution:
Capacity of the capacitor
Video Solution:
Q6 Text Solution:
According to question
Q3 Text Solution:
Video Solution:
Video Solution:
Q7 Text Solution:
Q = CV
C does not depen on Q and V
Q4 Text Solution: Q V
Video Solution:
Q8 Text Solution:
...(2)
on deviding (1) / (2)
we get
Q9 Text Solution:
Video Solution:
Capacitance is independent of voltage and
charge–depends only on A, d, . Both
statements are true and related.
Video Solution:
Q4 A circle of radius R is drawn in a uniform Q6 If a unit positive charge is taken from one
electric field E as shown in the fig. VA, VB, VC point to another over an equipotential surface,
and VD are respectively the potentials of points then
(A) Work is done on the charge
A, B, C and D on the circle then :-
(B) Work is done by the charge
(C) Work done is constant
(D) No work is done
(C)
(D) W = zero
Q2 A Q7 D
Q3 A Q8 A
Q4 C Q9 A
Q5 B Q10 A
Q1 Text Solution:
A and C lie on perpendicular to
inside conduction They are equipotential.
V remains same throughout the conductor.
Video Solution:
Video Solution:
Q5 Text Solution:
Q2 Text Solution: V1 –V2 = Ed cos60°
Potential Difference between inner and outer
Video Solution:
sphere will remain unchanged of the charges
kept on outer shell.
Video Solution:
Q6 Text Solution:
Video Solution:
Potential Difference
Video Solution:
Q7 Text Solution:
Surfaces are equipotential
VA = VB
W = q(VB – VA) = 0
Q4 Text Solution:
Video Solution:
VD > VB as V in direction of
Video Solution:
Q8 Text Solution:
Video Solution:
Q9 Text Solution:
For a point charge, potential at a distance r is
Q1 The distance between H+ and Cl– ions in HCl Q5 If an electric dipole is placed in an electric field
generated by a point charge then: -
molecule is 1.28Å What will be the potential
(A) the net electric force on the dipole must be
due to this dipole at a distance of 12Å on the
zero
axis of dipole
(B) the net electric force on the dipole may be
(A) 0.13 V (B) 1.3 V
zero
(C) 13V (D) 130V
(C) the torque on the dipole due to the field
Q2 must be zero
An electric dipole of dipole moment is
(D) the torque on the dipole due to the field
placed at the origin along the x -axis. The angle
may be zero
made by electric field with x-axis at a point P,
whose position vector makes an angle with Q6 An electric dipole is placed in non-uniform
Q2 C Q7 B
Q3 B Q8 B
Q4 A Q9 D
Q5 D Q10 C
Video Solution:
Q4 Text Solution:
Q2 Text Solution:
Video Solution:
Video Solution:
Video Solution:
Q6 Text Solution:
a force which must be non-zero
Video Solution:
Q9 Text Solution:
Potential Energy
Video Solution:
Q7 Text Solution:
Given
Video Solution:
Video Solution:
at C is
(A)
(B)
(C)
(D)
Q2 A Q7 C
Q3 D Q8 B
Q4 C Q9 C
Q5 B Q10 C
Q1 Text Solution:
One volt (1 V) is defined as the potential
difference between two points in a circuit
Video Solution:
when one joule (1 J) of work is done to move
one coulomb (1 C) of charge between those
points.
Video Solution:
Q4 Text Solution:
Q2 Text Solution:
The electric potential at a point due to a
charge q at a distance r is given by:
Video Solution:
Since potential is a scalar quantity, we can
directly add the contributions from both
=0 Q5 Text Solution:
Video Solution: By using
Video Solution:
Q3 Text Solution:
Q6 Text Solution:
Potential at mid-point
Q7 Text Solution:
Case-II
Video Solution:
Video Solution:
Q8 Text Solution:
Q1 Pick out the expression of electric potential Q4 Three point charges q, and q are placed
energy from the following. at the corners of an equilateral triangle of side
(A) a. The electrostatic potential energy of the
system is:
(B)
(A) (B)
(C)
(C) (D) Zero
(D) U
(C)
(A)
(B)
(C)
(D)
Q2 C Q7 C
Q3 D Q8 D
Q4 B Q9 B
Q5 C Q10 B
Video Solution:
Q4 Text Solution:
Total potential energy = sum of interaction
energies:
Q2 Text Solution:
Explanation: The sphere with radius R stores
more electric potential energy. According to Video Solution:
the electric potential energy equation
Potential energy is
U=
. But
Potential energy
2. Between charge q at B and charge -2q at 0:
Distance = a
Video Solution:
Video Solution:
Q7 Text Solution:
The electric potential energy of the positively
charged particle decreases as it moves in the
direction of the electric field.
Video Solution:
Utotal = U1 + U2 + U3
Video Solution:
PARISHRAM 2026
PHYSICS Assignment - 01
Q1 Assertion (A): Equal amount of positive and electric field of magnitude, will be at a
negative charges are distributed uniformly on
distance of
two halves of a thin circular ring as shown in
(A) 1 m (B) 2 m
figure. The resultant electric field at the centre
(C) 3 m (D) 6 m
O of the ring is along OC.
Reason (R): It is so because the net potential at Q4 A point P lies at a distance x from the mid
O is not zero. point of an electric dipole on its axis. The
electric field at point P is proportional to
(A) (B)
(C) (D)
(B) Always increase slightly (C) directed radially away from the point
(C) May increase or decrease slightly charge
(D) No change in weight (D) directed radially towards the point charge
Q8 In figure, two positive charges q2 and q3 fixed Q11 A positive charge Q is uniformly distributed
along the y axis, exert a net electric force in along a circular ring of radius R. A small test
the +x direction on a charge q1 fixed along the charge q is placed at the centre of the ring.
Then
x axis. If a positive charge Q is added at (x, 0)
the force on q1
(A) shall increase along the positive x-axis (A) if q > 0 and is displaced away from the
(B) shall decrease along the positive x-axis centre in the plane of the ring., it will be
(C) shall point along the negative x-axis pushed back towards the centre
(D) shall increase but the direction 2and3 (B) if q < 0 and is displaced away from the
changes because of the intersection q centre in the plane of the ring, it will never
of Q with q return to the centre and will continue
moving till it hits the ring
Q9 The electric flux through the surface
(C) if q < 0, it will perform SHM for small
displacement along the axis
(D) All of the above
(C)
(D)
Answer Key
Q1 C Q11 D
Q2 A Q12 A
Q3 C Q13 A
Q4 A Q14 A
Q5 A Q15 B
Q6 A Q16 C
Q7 C Q17 B
Q8 A Q18 D
Q9 D Q19 A
Q10 A Q20 D
Q1 Text Solution:
Electric field is from positive charge to negative
charge, hence the direction of electric field will which simplifies to:
be along OC. Also, the net potential at O is
zero. Hence, the assertion is true and the
reason is false. By cross-multiplying and solving for :
Video Solution:
Q4 Text Solution:
Expression for electric field due to dipole at
Or,
geueral point in given as
Or,
So,
Video Solution:
Video Solution:
Q3 Text Solution:
Q5 Text Solution:
Using the inverse square law relationship for
Since, electron and proton has opposite
electric fields from a point charge:
charge and moving in the same direction, So
there must be an attractive force between
them.
Substituting the known values: Video Solution:
Video Solution:
Q6 Text Solution:
Electric field is said to be conservative since,
work done in this field is path independent. It
depends on the end points only. So, in an
Q10 Text Solution:
electric field, total work done in moving a
directed perpendicular to the plane and away
charge from a point to the next point and
from the plane
again back to the first point is zero.
Video Solution:
Hence, assertion and reason both are true and
reason explains the assertion.
Video Solution:
Video Solution:
Video Solution:
Video Solution:
Video Solution:
Q17 Text Solution: of the point on the axis from the mid-point of
Force on any charge due to a number of other the dipole
charges is the vector sum of all the forces on We know that the electric field intensity due to
that charge due to the other charges, taken dipole on the given point (E)
one at a time. The individual force are
unaffected due to the presence of other
charges. This is the principle of superposition
of charges.
Video Solution:
Video Solution:
Video Solution:
Q19 Text Solution:
Given : Length of the dipole
0.05 m
Charge on the dipole
and distance
Q1 The electric field due to a continuous charge Q5 The electric field at a point on the axis of a
distribution depends on: uniformly charged ring of radius R and total
(A) The geometry of the charge distribution charge Q is:
and the location of the point of interest (A) (B)
(B) Only the total charge
(C) Only the distance from the charge (C) (D)
(D) None of the above
Q2 For a charge distribution with a volume charge Q6 An electron and a proton are at distance of 1Å .
density , the total charge in a spherical The moment of this dipole will be (C × m)
volume of radius R is given by: (A) 1.6 ×
(A) (B) 1.6 ×
(B) (C) 3.2 ×
(D) 3.2 ×
(C)
(D) Q7 A given charge is situated at a certain distance
from an electric dipole in the end-on position
Q3 The surface charge density is defined as:
experiences a force F. If the distance of the
(A) Charge per unit volume
charge is doubled, the force acting on the
(B) Charge per unit length
charge will be
(C) Charge per unit area
(A) 2F (B) F/2
(D) Charge per unit time
(C) F/4 (D) F/8
Q4 A uniformly charged infinite line of charge with
Q8 The spatial distribution of the electric field
linear charge density creates an electric field
lines due to charges (A, B) is shown in figure.
at a point a distance r from the line. If the
Which one of the following statements is
electric field at this point is E, what will happen correct?
to the electric field if the linear charge density
is doubled?
(A) The electric field will increase by a factor of
2.
(B) The electric field will increase by a factor of
4.
(C) The electric field will decrease by a factor of
(A) A is +ve and B is -ve and |A| > |B|
2.
(B) A is – ve and B is + ve; |A| = |B|
(D) The electric field will remain unchanged.
Q2 B Q7 D
Q3 C Q8 A
Q4 A Q9 B
Q5 A
Video Solution:
Q5 Text Solution:
The electric field at a point on the axis of a
Q2 Text Solution:
uniformly charged ring at a distance x from the
The total charge in a spherical volume with
centre of the ring is given by the equation:
radius R and volume charge density is given
by the volume of the sphere multiplied
by . Video Solution:
Thus,
Video Solution:
Q6 Text Solution:
Q3 Text Solution:
Surface charge density is the charge per unit
Video Solution:
area, typically expressed as , where Q
is the charge and A is the surface area.
Video Solution:
Q7 Text Solution:
Q4 Text Solution:
Video Solution:
Q9 Text Solution:
(C)
(D)
(C) (D)
(C) (D)
Q2 D Q7 C
Q3 C Q8 C
Q4 A Q9 A
Q5 A Q10 D
Q1 Text Solution:
The electric flux is
Substituting the values:
Video Solution:
Q2 Text Solution:
Gauss’s Law can be used to derive the electric
field due to a point charge, spherical shell, and
infinite plane sheet. However, it cannot
directly be applied to charged conductors
unless symmetry is considered. Coulomb’s Law
is typically used to calculate the electric field Q5 Text Solution:
for such conductors.
By Gauss's theorem. Total flux
Video Solution:
So the flux through one face
Video Solution:
Q3 Text Solution:
At any point over the spherical Gaussian
surface, net electric field is the vector sum of Q6 Text Solution:
electric fields due to +q2, q1 and q2. Don't Total flux coming out form unit charge
confuse with the electric flux which is zero
(net) passing over the Gaussian surface as the
Video Solution:
net charge enclosing the surface is zero.
Video Solution:
Q7 Text Solution:
S.I. unit of electric flux is Q9 Text Solution:
The assertion is true because the flux through
a spherical surface surrounding a point charge
Video Solution: is the same regardless of the size of the
sphere. The reason is also true because
Gauss’s Law states that the flux depends only
on the charge enclosed, not on the radius of
the sphere.
Video Solution:
Q8 Text Solution:
To apply Gauss's theorem it is essential that
charge should be placed inside a closed
surface. So imagine another similar cylindrical
vessel above it as shown in figure (dotted).
Video Solution:
Q1 When a glass rod is rubbed with silk, the glass (B) Induced charge and electrostatic force
rod becomes: (C) Gravitational attraction
(A) Negatively charged (D) Surface tension
(B) Positively charged
Q7 Assertion (A): The electrostatic force between
(C) Neutral
two charges increases if the distance between
(D) Electrically inert
them is decreased.
Q2 Which of the following is true about charging Reason (R): According to Coulomb's Law, force
by friction? is inversely proportional to the square of the
(A) Both bodies always lose charge distance between charges.
(B) Electrons are transferred from one body to (A) Both A and R are true, and R is the correct
another explanation of A
(C) Protons are transferred (B) Both A and R are true, but R is not the
(D) Neutrons are transferred correct explanation of A
(C) A is true but R is false
Q3 During charging by friction, the total charge of
(D) A is false but R is true
the system:
(A) Increases Q8 Assertion (A): Electrostatic force between
(B) Decreases charges is greater in vacuum than in water.
(C) Remains conserved Reason (R): Water has a high dielectric
(D) Becomes zero constant which reduces the force between
charges.
Q4 The electrostatic force is a:
(A) Both A and R are true, and R is the correct
(A) Non-conservative and contact force
explanation of A
(B) Conservative and long-range force
(B) Both A and R are true, but R is not the
(C) Short-range and non-conservative force
correct explanation of A
(D) Gravitational type short-range force
(C) A is true but R is false
Q5 If the distance between two charges is tripled, (D) A is false but R is true
the force becomes:
Q9 There are two charges +1 microcoulomb and
(A) (B)
+5 microcoulomb. The ratio of the forces
(C) 3 times (D) 9 times acting on them will be
(A) 1: 5 (B) 1: 1
Q6 When a balloon is rubbed with hair, it sticks to
(C) 5: 1 (D) 1 : 25
the wall. This is due to:
(A) Magnetic attraction
Q2 B Q7 A
Q3 C Q8 A
Q4 B Q9 B
Q5 A Q10 A
Q5 Text Solution:
Q2 Text Solution:
Electrons are transferred from one body to
another
Only electrons are mobile. Friction causes Video Solution:
electrons to be transferred from one body to
another.
Video Solution:
Q6 Text Solution:
Induced charge and electrostatic force
The charged balloon induces opposite charges
Q3 Text Solution: on the wall, causing electrostatic attraction.
Remains conserved Video Solution:
Law of conservation of charge – the total
charge before and after friction remains
constant.
Video Solution:
Q7 Text Solution:
Coulomb's Law: , so decreasing
distance increases the force. The reason
directly explains the assertion.
Q4 Text Solution:
Video Solution:
Q8 Text Solution:
In Coulomb's law with a medium: Q10 Text Solution:
In second case, charges will be
Video Solution:
Video Solution:
Q9 Text Solution:
The same force will act on both bodies
although their directions will be different.
Q2 D Q7 A
Q3 D Q8 D
Q4 B Q9 B
Q5 B Q10 D
Video Solution:
Q5 Text Solution:
When a body is earth-connected and electrons
flow from the earth into the body, it means:
Q2 Text Solution:
• The body is positively charged initially.
In Millikan's oil drop experiment, the charge
• To neutralize this positive charge, electrons
on an oil drop is always a multiple of the
from the earth move into the body.
elementary charge, which is approximately e =
Video Solution:
1.6 × 10–19 C.
Since none of the given charges are integer
multiples of the elementary charge, none of
them can be present on an oil drop.
Video Solution:
Q6 Text Solution:
Q=n×e
Q = 1014 × 1.6 × 10–19
Q = 1.6 × 10–5 C
Q3 Text Solution: Q = 16µC
The induced charge distribution is non- When electrons are removed, the sphere
uniform but the net charge of the sphere itself becomes positively charged.
remains zero. Video Solution:
Video Solution:
Q7 Text Solution:
Video Solution:
Q1 The unit of electric field intensity is....... They represent the path a positive test charge
(A) N/C would follow in an electric field.
(B) V/m (D) The density of lines of force increases with
(C) Both (A) and (B) the strength of the electric field.
(D) None of these
Q6 Which of the following is true about the electric
Q2 The field due to a charge at a distance 'x' from it lines of force?
is 'E'. When the distance is doubled, the intensity (A) They never intersect each other.
of the field is (B) They form closed loops.
(A) E/8 (B) E (C) They always point towards the positive
(C) 2E (D) E/4 charge.
(D) They do not depend on the magnitude of the
Q3 The magnitude of electric field intensity E is such
charge.
that, an electron placed in it would experience an
electrical force equal to its weight is given by Q7 The electric field lines due to a positive point
mg
(A) mge (B) e
charge:
(C) (D) (A) Point radially outward from the charge.
2
e e
g
mg 2
m
(B) Point radially inward towards the charge.
Q4 A drop of 10 −6
kg water carries 10 −6
C charge. (C) Form closed loops around the charge.
What electric field should be applied to balance (D) Are parallel to each other.
its weight (assume g = 10 m/s
2
)
(A) 10 V/m upward Q8 Some electric lines of force are shown in figure,
(B) 10 V/m downward for point A and B.
(C) 0.1 V/m downward
(D) 0.1 V/m upward
1/6
(B) Both assertion and reason are true, but the
reason is not the correct explanation of the
assertion
(C) Assertion is true, but reason is false.
(D) Assertion is false, but reason is true.
(A) EA > EB
(B) EA < EB
(C) EA = EB
2/6
Answer Key
Q1 (C) Q6 (A)
Q2 (D) Q7 (A)
Q3 (B) Q8 (A)
Q4 (A) Q9 (A)
3/6
Hints & Solutions
Note: scan the QR code to watch video solution
Video Solution:
Q5 Text Solution:
Electric lines of force do not form closed loops.
Video Solution:
Q6 Text Solution:
Electric lines of force do not intersect each other,
as this would imply that the electric field has two
directions at a point, which is impossible.
Q3 Text Solution:
According to the question, Video Solution:
mg
eE = mg ⇒ E =
e
Video Solution:
Q7 Text Solution:
The electric field lines due to a positive point
charge radiate outward from the charge.
Q4 Text Solution:
By using QE = mg Video Solution:
mg −6
; upward
10 ×10
⇒ E = = = 10 V /m
−6
Q 10
4/6
Q8 Text Solution:
Lines are denser at A. so EA > EB
Video Solution:
Q9 Text Solution:
Both are negative
Video Solution:
Video Solution:
5/6
CHEMISTRY 112 WORKSHEET
NOMENCLATURE OF COORDINATION COMPOUNDS AND IONS
B. Write the formula for each of the following complex compounds or ions.