Solution
Solution
2401CJA101001250016 JA
PART-1 : PHYSICS
SECTION - I (i)
1) Two masses are connected by a string which passes over a pulley accelerating upward at a rate 5
m/s2 as shown. If aceleration of mass 1 is a1 = 2 m/s2 upwards then the acceleration of mass 2 is :-
2) Two persons A and B are sitting in two cars 1 and 2 such that the velocity of the cars is given by
(A)
(B)
(C)
(D)
3) If velocity of block B in the given figure is 300mm/s towards right. Then velocity of A will be :-
4) An object starts moving from rest on a circle of radius 2m, with constant tangential acceleration
2m/s2. The time after which acceleration of object makes angle 45° from tangent is
(A) 1 sec
(B) 2 sec
(C)
(D)
SECTION - I (ii)
1) In the system shown in the figure m1 > m2 . System is held at rest by thread BC . Just after the
thread BC is burnt :
(B)
Magnitude of acceleration of both blocks will be equal to g
(C) Acceleration of m1 will be equal to zero
(D) Magnitude of acceleration of two blocks will be non-zero and unequal.
(A)
(B)
SECTION - I (iii)
(A) aω cos ωt
(B) aω
(C) aω sin ωt
(D) None
(A) aω2
(B) aω
(C)
(D)
(A)
upwards
(B)
upwards
(C)
upwards
(D)
upwards
(A)
mg
(B)
mg
(C)
mg
(D)
mg
SECTION - II
1) With what minimum acceleration (in m/s2) mass M must be moved on frictionless surface so that
m remains at rest with respect to 'M' as shown. The coefficient of friction between M and m is 0.4. (g
= 10 m/s2)
2) A 5kg block has a uniform rope of mass 2kg attached to its underside and a 3kg block is
suspended from the other end of the rope. An external force of 80N is applied on the 5kg block in
upward direction as shown in figure. If T is tension at mid point of rope and whole system is in mid
air above the surface. Find the value of T (in N).
3) A block of mass 2 kg is resting over another block of mass 6 kg. 2 kg block is connected to one
end of a string fixed to a vertical wall as shown. If the coefficient of friction between the block is 0.4,
the force (in N) required to pull out the 6 kg block with an acceleration of 1.5 m/s2 is ________ (g = 10
ms–2)
4) Two blocks of masses 2 kg and 3 kg are placed in a lift which moves up with an upward
acceleration of a = 2 m/s2 as shown in figure. If an external force of 15 N is acting on 2 kg block, find
5) A disk rotates about its central axis starting form rest and accelerates with constant angular
acceleration. At one instant it is rotating at 12 rad/s and after 80 radian of more angular
displacement, its angular speed becomes 28 rad/s. How much time (seconds) does the disk takes to
complete the mentioned angular displacement of 80 radians.
6) A particle is moving with constant speed in a circular path. The ratio of average velocity to its
SECTION - I (i)
(A) Statement-1 is true, statement-2 is true and statement-2 is correct explanation for statement-1.
Statement-1 is true, statement-2 is true and statement-2 is NOT the correct explanation for
(B)
statement‑1.
(C) Statement-1 is true, statement-2 is false.
(D) Statement-1 is false, statement-2 is true.
3) Moles of ABC3 produced in the following set of reaction when 180 gm of A, 180gm of B and 200
gm of C are mixed in a container (given molar masses of A,B,C are 20, 30 & 10 respectively.
2A + 3B + 5C → A2BC2 + B2C3
B2C3 + 3C → 2BC3
BC3 + A → ABC3
(A) 5
(B) 4
(C) 10/3
(D) 20/3
(A) 201.6 L
(B) 100.8 L
(C) 403.2 L
(D) 50.4 L
SECTION - I (ii)
1) 5.6 g N2(g) and 0.6 g H2(g) is taken to react and form NH3(g).
N2(g) + 3H2(g) → 2NH3(g)
CORRECT statements is/are -
(A)
(B)
(C)
(D)
SECTION - I (iii)
(A) 16 gm
(B) 3.2 gm
(C) 1.6 gm
(D) 32 gm
4) If 3 × 1022 molecules of O2 are added in vessel. Find the new pressure in vessel at same
temperature in vessel-
SECTION - II
2) The weight (in gram ) of pure potash Alum (K2SO4.Al2(SO4)3.24H2O) which contains 6.4 gm oxygen
is.
(Atomic weight of K = 39, S = 32, Al = 27)
3) The Kohinoor diamond was the largest diamond ever found. How many moles of carbon atom
were peresent in it, if it is weigh 3300 carat. [Given: 1 carat = 200 mg]
5) Find the number of molecules in which atleast two d-orbitals are involved in hybridisation :-
XeF5–, SF4, XeF6 , SO3F–, CF4 , SO3 , , IF7
PART-3 : MATHEMATICS
SECTION - I (i)
1) Let a, b are roots of the equation x2 – 3x + p = 0 and c, d are roots of the equation x2 – 12x + q =
(A)
(B)
(C)
(D)
(A) 2
(B) 3
(C) 6
(D) 9
(A) A=2B
(B) A=1/3B
(C) A=B
(D) 3A=2B
(A) x4+y4=9
(B)
(C) x3+y3=2(x2+y2)
(D)
SECTION - I (ii)
(A)
tan2x =
(B)
tan2x =
(C)
(D)
2) If & , then P2 + Q2 is -
3) Let , then
(A) S9 is divisible by 4
(B) S9 is divisible by 21
10
(C) 10.S10+3 = 3
(D) 7(S7 + 3), 10(S10 + 3), 13(S13+ 3) are in G.P.
SECTION - I (iii)
(A) 3
(B) 4
(C) 7
(D) 10
(A) 20300
(B) 21300
(C) 22300
(D) 23300
(A)
(B)
(C)
(D)
(A)
(B)
(C)
(D)
SECTION - II
1) Value of is equal to
2) If x = cos α + cos β – cos(α + β) and y = 4 sin sin cos , then (x–y) equals
4)
If a, b, c are positive real numbers and the minimum value of
5) is equal to
6) Let Tn be the nth term of a series for n ≥ 1 and T1 = 1, Tn + 1 = 2Tn + 4n, n ≥ 1. If Sn = Sum of first n
PART-1 : PHYSICS
SECTION - I (i)
Q. 1 2 3 4
A. C B A A
SECTION - I (ii)
Q. 5 6 7
A. A,C C,D A,B,C
SECTION - I (iii)
Q. 8 9 10 11
A. B A A C
SECTION - II
Q. 12 13 14 15 16 17
A. 25.00 32.00 17.00 9.00 4.00 2.00
PART-2 : CHEMISTRY
SECTION - I (i)
Q. 18 19 20 21
A. C C B A
SECTION - I (ii)
Q. 22 23 24
A. A,B,C C,D B,C
SECTION - I (iii)
Q. 25 26 27 28
A. B D C A
SECTION - II
Q. 29 30 31 32 33 34
A. 3.20 9.48 55.00 3.00 3.00 3.00
PART-3 : MATHEMATICS
SECTION - I (i)
Q. 35 36 37 38
A. B D C D
SECTION - I (ii)
Q. 39 40 41
A. B,C A,C A,B,D
SECTION - I (iii)
Q. 42 43 44 45
A. A D A D
SECTION - II
Q. 46 47 48 49 50 51
A. 2.00 1.00 7.00 0.20 1.50 1.50
SOLUTIONS
PART-1 : PHYSICS
1)
From constant relation
a1 + a2 = 2a3
2) = 6ti – 8t5j
at t = 1 sec ; = 6i – 8j
= – 50 [6i – 8j]
= 50 [8j – 6i]
= 100 [4j – 3i]
3)
2TVb = 3TVa
Va =
4)
= 2.
=2
t = 1sec
5)
T = m1g
for m1 a=o
6)
F.B.D. of trolley is w.r.t. ground
F.B.D. of suspended mass is w.r.t. Trolley.
Tcos 37° – mg = 0 [Equilibrium of mass in y direction w.r.t. trolley]
⇒T= T = 25 N
T sin 37° – ma = 0 [Equilibrium of mass in x direction w.r.t. trolley]
⇒a= =
F – T sin37° = 8a [Newton’s II law for trolley in x direction w.r.t. ground]
⇒F=8× + 25 × F = 75 N
7)
Ans. (A,B,C)
A,B,C is the correct answer
8)
Ans. (B)
B is the correct answer
|v| = aω
ax = –aω2 sin ωt
ay = aω2 cos ωt
11)
Balacing force for A in Hz direction
F = N' sin 37° ⇒
...... (i)
Balancing force for B in vertical direction
N'cos 37° + N3 = mg
N' cos 37° + N3 = mg
for lifting the black B N3 = 0
N' cos 37° = mg ...... (ii)
12)
N = ma .......(1)
f = mg
f ≤ fs max
mg ≤ µN
mg ≤ µma
a≥
a ≥ 25
amin =
13)
10g – 80 = 10a
a = 2 m/s2
T + 60 – 80 = 6a
T = 6 × 2 + 20
T = 32N
14)
F = 0.4 × 2 × 10 = 8 N
F – 8 = 6 × 1.5
F = 17 N
N + 15 – 20 = 2 × 2
⇒ N = 5 + 4 = 9 Newtons
16)
17)
PART-2 : CHEMISTRY
18)
19)
decided by
I > II size of Surrounding Atom
I < IV size of Hybrid orbital
I=V same
III > I &V size of Surrounding Atom
III > IV size of Surrounding Atom
20)
21)
volume of H2 =
22)
N2(g) + 3H2(g) → 2NH3(g)
Initial 0.2 mole 0.3 mole
Ratio >
(mole/SC)
H2 is L.R.
Final 0.1 mole 0 mole 0.2 mole
24)
25)
29)
60 gm CH3COOH has 32 gm O
6 gm CH3COOH will hvae 3.2 gm O-atoms
Moles of carbon =
32)
Ans. (3.00)
(3.00) is the correct answer
33)
XeF5 → sp3d3
SF4 → sp3d
XeF6 → sp3d3
→ sp3
CF4 → sp3
SO3 → sp2
→
sp3d
IF7 → sp3d3
34)
y=1
z = 14
PART-3 : MATHEMATICS
35) a + b = 3 ; ab = p
c + d = 12 ; cd = q
Let a = a,
b = ar
c = ar2
and d = ar3
∴
⇒ r = ±2
so,
36)
37) We have
⇒ tan6°tan42°tan66°tan78° ×
⇒
[∴ tan(60° – θ)tanθ tan(60° + θ) = tan3θ]
⇒
⇒A=B
x=
y=
x = 2 (1 + sin2θ ) – cos22θ ;
y = 2 (1 – sin2θ) – cos22θ
x = 1 + 2 sin2θ + sin22θ ;
y = 1 – 2 sin2θ + sin22θ
x = (1 + sin2θ)2 ;
y = (1 – sin2θ)2
39)
⇒
⇒ 8(5 sin4x + 3 + 3 sin4x – 6 sin2x) = 15
⇒ 64sin4x – 48 sin2x + 9 = 0
(8 sin2x – 3)2 = 0
∴ tan2x = ⇒ (B)
⇒ ⇒ (C)
40)
&
41)
(A) (B) S9 = 37 – 3 = 3(272 – 1) = 3.26.28
(C)
(D) n(Sn + 3) = 3n
so 37, 310,313 are in G.P.
42)
n can't be
⇒ either ans. is 2 or 3
value at 2 is –15
value at 3 is
Hence minimum value occure at n = 2
⇒
⇒a+b=3
43)
Sn = ƒ(Sn–1)
⇒ T2 = 15
⇒ T3 = 25
Tn = 10n – 5
Sn = 5n2 T2018 + S25 = 23300
.....(1)
....(2)
⇒
45)
46) =
47)
49)
Let Sn = 1 + 4 + 10 + 20 + 35 + 56 +..... + Tn
Sn = 1 + 4 + 10 + 20 + 35 +..... + Tn
Tn = 1 + 3 + 6 + 10 + 15 + 21 +..... + tn
Tn = 1 + 3 + 6 + 10 + 15 +..... + tn
tn = 1 + 2 + 3 + 4 +..... n terms
Now
51)
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