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Page 1
1
FINAL JEE –MAIN EXAMINATION – JUNE, 2022
(Held On Tuesday 28
th
June, 2022) TIME : 3 : 00 PM to 6 : 00 PM
PHYSICS TEST PAPER WITH SOLUTION
SECTION-A
1. Velocity (v) and acceleration (a) in two systems of
units 1 and 2 are related as ?
21 2
n
vv
m
and
1
2
a
a
mn
? respectively. Here m and n are
constants. The relations for distance and time in
two systems respectively are:
(A)
32
1 2 1 2 3
nn
L L and T T
mm
??
(B)
42
1 2 1 2 2
nn
L L andT T
mm
??
(C)
24
1 2 1 2 2
nn
L L and T T
mm
??
(D)
24
1 2 1 2 2
nn
L L and T T
mm
??
Official Ans. by NTA (A)
Sol.
21
2
21
LL n
TT m
?
21
22
21
LL
T T mn
?
?
2
22
22
1 1
TT n
T m T mn
??
?
2
2
1
T n
mT
?
4
2
2
1
L n1
L mn m
??
3
2
3
1
L n
L m
?
2. A ball is spun with angular acceleration
? ? ?
2
6t 2t where t is in second and ? is in
rads
–2
. At t = 0, the ball has angular velocity of 10
rads
–1
and angular position of 4 rad. The most
appropriate expression for the angular position of
the ball is:
(A)
42
3
t t 10t
2
??
(B)
43
tt
10t 4
23
? ? ?
(C)
43
2t t
10t 12
36
? ? ?
(D)
3
4
t
2t 5t 4
2
? ? ?
Official Ans. by NTA (B)
Sol.
2
dw
6t 2t
dt
??
w
32
10
dw 2t t ??
?
32
w 10 2t t ? ? ?
32
d
10 2t t
dt
?
? ? ?
32
4
d 10 2t t
?
? ? ? ?
?
?
? ? ? ?
?
43
4
tt
d 10t
23
43
tt
4 10t
23
? ? ? ? ?
Page 2
1
FINAL JEE –MAIN EXAMINATION – JUNE, 2022
(Held On Tuesday 28
th
June, 2022) TIME : 3 : 00 PM to 6 : 00 PM
PHYSICS TEST PAPER WITH SOLUTION
SECTION-A
1. Velocity (v) and acceleration (a) in two systems of
units 1 and 2 are related as ?
21 2
n
vv
m
and
1
2
a
a
mn
? respectively. Here m and n are
constants. The relations for distance and time in
two systems respectively are:
(A)
32
1 2 1 2 3
nn
L L and T T
mm
??
(B)
42
1 2 1 2 2
nn
L L andT T
mm
??
(C)
24
1 2 1 2 2
nn
L L and T T
mm
??
(D)
24
1 2 1 2 2
nn
L L and T T
mm
??
Official Ans. by NTA (A)
Sol.
21
2
21
LL n
TT m
?
21
22
21
LL
T T mn
?
?
2
22
22
1 1
TT n
T m T mn
??
?
2
2
1
T n
mT
?
4
2
2
1
L n1
L mn m
??
3
2
3
1
L n
L m
?
2. A ball is spun with angular acceleration
? ? ?
2
6t 2t where t is in second and ? is in
rads
–2
. At t = 0, the ball has angular velocity of 10
rads
–1
and angular position of 4 rad. The most
appropriate expression for the angular position of
the ball is:
(A)
42
3
t t 10t
2
??
(B)
43
tt
10t 4
23
? ? ?
(C)
43
2t t
10t 12
36
? ? ?
(D)
3
4
t
2t 5t 4
2
? ? ?
Official Ans. by NTA (B)
Sol.
2
dw
6t 2t
dt
??
w
32
10
dw 2t t ??
?
32
w 10 2t t ? ? ?
32
d
10 2t t
dt
?
? ? ?
32
4
d 10 2t t
?
? ? ? ?
?
?
? ? ? ?
?
43
4
tt
d 10t
23
43
tt
4 10t
23
? ? ? ? ?
2
3. A block of mass 2 kg moving on a horizontal
surface with speed of 4 ms
-1
enters a rough surface
ranging from x = 0.5 m to x = 1.5 m. The retarding
force in this range of rough surface is related to
distance by F kx ?? where k = 12 Nm
-1
. The
speed of the block as it just crosses the rough
surface will be:
(A) Zero (B) 1.5 ms
-1
(C) 2.0 ms
-1
(D) 2.5 ms
-1
Official Ans. by NTA (C)
Sol.
kx 12x
a 6x
22
??
? ? ? ?
vdv
6x
dx
??
v 3/2
1 4
2
vdv 6xdx ??
??
22
22
v 4 6 3 1
2 2 2 2
??
? ? ? ? ?
? ? ? ??
? ? ? ?
? ? ? ? ??
??
2
91
v 16 6
44
??
? ? ? ?
??
??
2
v 16 6 2 4 ? ? ? ?
V = 2 m/s
4. A 34 m long ladder weighing 10 kg leans on a
frictionless wall. Its feet rest on the floor 3 m away
from the wall as shown in the figure. If F
f
and F
w
are the reaction forces of the floor and the wall,
then ratio of F
w
/F
f
will be:
(Use g = 10 m/s
2
)
(A)
6
110
(B)
3
113
(C)
3
109
(D)
2
109
Official Ans. by NTA (C)
Sol.
34m
N
2
S
3m
mg
N
1
f
?
?
2
fN
1
N mg ?
2
N sin mg cos
2
? ? ? ?
2
mg
N cot
2
??
? ?
w
2
f
2
mg
cot
F
2
F
mg
mg cot
2
?
?
??
??
??
??
2
1
4
1
cot
?
?
?
3
109
?
5. Water fall from a 40 m high dam at the rate of
?
4
9 10 kg per hour. Fifty percentage of
gravitational potential energy can be converted into
electrical energy. Using this hydroelectric energy
number of 100W lamps, that can be lit, is:
(Take g = 10 ms
-2
)
(A) 25 (B) 50
(C) 100 (D) 18
Official Ans. by NTA (B)
Sol.
4
9 10 g 40
0.5 n 100
3600
? ? ?
? ? ?
4
10 0.5
n
100
?
?
100 × 0.5 = n
n = 50
Page 3
1
FINAL JEE –MAIN EXAMINATION – JUNE, 2022
(Held On Tuesday 28
th
June, 2022) TIME : 3 : 00 PM to 6 : 00 PM
PHYSICS TEST PAPER WITH SOLUTION
SECTION-A
1. Velocity (v) and acceleration (a) in two systems of
units 1 and 2 are related as ?
21 2
n
vv
m
and
1
2
a
a
mn
? respectively. Here m and n are
constants. The relations for distance and time in
two systems respectively are:
(A)
32
1 2 1 2 3
nn
L L and T T
mm
??
(B)
42
1 2 1 2 2
nn
L L andT T
mm
??
(C)
24
1 2 1 2 2
nn
L L and T T
mm
??
(D)
24
1 2 1 2 2
nn
L L and T T
mm
??
Official Ans. by NTA (A)
Sol.
21
2
21
LL n
TT m
?
21
22
21
LL
T T mn
?
?
2
22
22
1 1
TT n
T m T mn
??
?
2
2
1
T n
mT
?
4
2
2
1
L n1
L mn m
??
3
2
3
1
L n
L m
?
2. A ball is spun with angular acceleration
? ? ?
2
6t 2t where t is in second and ? is in
rads
–2
. At t = 0, the ball has angular velocity of 10
rads
–1
and angular position of 4 rad. The most
appropriate expression for the angular position of
the ball is:
(A)
42
3
t t 10t
2
??
(B)
43
tt
10t 4
23
? ? ?
(C)
43
2t t
10t 12
36
? ? ?
(D)
3
4
t
2t 5t 4
2
? ? ?
Official Ans. by NTA (B)
Sol.
2
dw
6t 2t
dt
??
w
32
10
dw 2t t ??
?
32
w 10 2t t ? ? ?
32
d
10 2t t
dt
?
? ? ?
32
4
d 10 2t t
?
? ? ? ?
?
?
? ? ? ?
?
43
4
tt
d 10t
23
43
tt
4 10t
23
? ? ? ? ?
2
3. A block of mass 2 kg moving on a horizontal
surface with speed of 4 ms
-1
enters a rough surface
ranging from x = 0.5 m to x = 1.5 m. The retarding
force in this range of rough surface is related to
distance by F kx ?? where k = 12 Nm
-1
. The
speed of the block as it just crosses the rough
surface will be:
(A) Zero (B) 1.5 ms
-1
(C) 2.0 ms
-1
(D) 2.5 ms
-1
Official Ans. by NTA (C)
Sol.
kx 12x
a 6x
22
??
? ? ? ?
vdv
6x
dx
??
v 3/2
1 4
2
vdv 6xdx ??
??
22
22
v 4 6 3 1
2 2 2 2
??
? ? ? ? ?
? ? ? ??
? ? ? ?
? ? ? ? ??
??
2
91
v 16 6
44
??
? ? ? ?
??
??
2
v 16 6 2 4 ? ? ? ?
V = 2 m/s
4. A 34 m long ladder weighing 10 kg leans on a
frictionless wall. Its feet rest on the floor 3 m away
from the wall as shown in the figure. If F
f
and F
w
are the reaction forces of the floor and the wall,
then ratio of F
w
/F
f
will be:
(Use g = 10 m/s
2
)
(A)
6
110
(B)
3
113
(C)
3
109
(D)
2
109
Official Ans. by NTA (C)
Sol.
34m
N
2
S
3m
mg
N
1
f
?
?
2
fN
1
N mg ?
2
N sin mg cos
2
? ? ? ?
2
mg
N cot
2
??
? ?
w
2
f
2
mg
cot
F
2
F
mg
mg cot
2
?
?
??
??
??
??
2
1
4
1
cot
?
?
?
3
109
?
5. Water fall from a 40 m high dam at the rate of
?
4
9 10 kg per hour. Fifty percentage of
gravitational potential energy can be converted into
electrical energy. Using this hydroelectric energy
number of 100W lamps, that can be lit, is:
(Take g = 10 ms
-2
)
(A) 25 (B) 50
(C) 100 (D) 18
Official Ans. by NTA (B)
Sol.
4
9 10 g 40
0.5 n 100
3600
? ? ?
? ? ?
4
10 0.5
n
100
?
?
100 × 0.5 = n
n = 50
3
6. Two objects of equal masses placed at certain
distance from each other attracts each other with a
force of F. If one-third mass of one object is
transferred to the other object, then the new force
will be :
(A)
2
F
9
(B)
16
F
9
(C)
8
F
9
(D) F
Official Ans. by NTA (C)
Sol.
2
2
Gm
F
r
?
2
4m 2m
G
33
F'
r
? ? ? ?
?
? ? ? ?
? ? ? ?
?
8
F' F
9
?
7. A water drop of radius ? 1m falls in a situation
where the effect of buoyant force is negligible. Co-
efficient of viscosity of air is
??
?
52
1.8 10 Nsm and
its density is negligible as compared to that of
water
? 63
10 gm . Terminal velocity of the water
drop is:
(Take acceleration due to gravity = 10 ms
–2
)
(A)
??
?
61
145.4 10 ms (B)
??
?
61
118.0 10 ms
(C)
??
?
61
132.6 10 ms (D)
??
?
61
123.4 10 ms
Official Ans. by NTA (D)
Sol.
F = 6 rv
vt
??
4
mg
3
=
?? rg
3
v
t
3
t
4
6 rv r g
3
? ? ? ? ?
3
t
4 r g
v
3 6 r
??
??
??
3 12 3
t –5
4 r g 2 10 10 10
v
3 6 r 9 1.8 10
?
? ? ? ? ?
? ? ?
?? ??
= 123.4 × 10
–6
m/s
8. A sample of an ideal gas is taken through the
cyclic process ABCA as shown in figure. It
absorbs, 40 J of heat during the part AB, no heat
during BC and rejects 60J of heat during CA. A
work 50J is done on the gas during the part BC.
The internal energy of the gas at A is 1560J. The
work done by the gas during the part CA is:
(A) 20 J (B) 30 J
(C) –30J (D) –60 J
Official Ans. by NTA (B)
Sol.
cycle
Q 40 60 W ? ? ? ? ?
BC CA
W – 2 0J W W ? ? ? ? ?
CA BC
W – 2 0 J W ? ? ?
= –20 – (–50)
= 30 J
9. What will be the effect on the root mean square
velocity of oxygen molecules if the temperature is
doubled and oxygen molecule dissociates into
atomic oxygen?
(A) The velocity of atomic oxygen remains same
(B) The velocity of atomic oxygen doubles
(C) The velocity of atomic oxygen becomes half
(D) The velocity of atomic oxygen becomes four
times
Official Ans. by NTA (B)
Page 4
1
FINAL JEE –MAIN EXAMINATION – JUNE, 2022
(Held On Tuesday 28
th
June, 2022) TIME : 3 : 00 PM to 6 : 00 PM
PHYSICS TEST PAPER WITH SOLUTION
SECTION-A
1. Velocity (v) and acceleration (a) in two systems of
units 1 and 2 are related as ?
21 2
n
vv
m
and
1
2
a
a
mn
? respectively. Here m and n are
constants. The relations for distance and time in
two systems respectively are:
(A)
32
1 2 1 2 3
nn
L L and T T
mm
??
(B)
42
1 2 1 2 2
nn
L L andT T
mm
??
(C)
24
1 2 1 2 2
nn
L L and T T
mm
??
(D)
24
1 2 1 2 2
nn
L L and T T
mm
??
Official Ans. by NTA (A)
Sol.
21
2
21
LL n
TT m
?
21
22
21
LL
T T mn
?
?
2
22
22
1 1
TT n
T m T mn
??
?
2
2
1
T n
mT
?
4
2
2
1
L n1
L mn m
??
3
2
3
1
L n
L m
?
2. A ball is spun with angular acceleration
? ? ?
2
6t 2t where t is in second and ? is in
rads
–2
. At t = 0, the ball has angular velocity of 10
rads
–1
and angular position of 4 rad. The most
appropriate expression for the angular position of
the ball is:
(A)
42
3
t t 10t
2
??
(B)
43
tt
10t 4
23
? ? ?
(C)
43
2t t
10t 12
36
? ? ?
(D)
3
4
t
2t 5t 4
2
? ? ?
Official Ans. by NTA (B)
Sol.
2
dw
6t 2t
dt
??
w
32
10
dw 2t t ??
?
32
w 10 2t t ? ? ?
32
d
10 2t t
dt
?
? ? ?
32
4
d 10 2t t
?
? ? ? ?
?
?
? ? ? ?
?
43
4
tt
d 10t
23
43
tt
4 10t
23
? ? ? ? ?
2
3. A block of mass 2 kg moving on a horizontal
surface with speed of 4 ms
-1
enters a rough surface
ranging from x = 0.5 m to x = 1.5 m. The retarding
force in this range of rough surface is related to
distance by F kx ?? where k = 12 Nm
-1
. The
speed of the block as it just crosses the rough
surface will be:
(A) Zero (B) 1.5 ms
-1
(C) 2.0 ms
-1
(D) 2.5 ms
-1
Official Ans. by NTA (C)
Sol.
kx 12x
a 6x
22
??
? ? ? ?
vdv
6x
dx
??
v 3/2
1 4
2
vdv 6xdx ??
??
22
22
v 4 6 3 1
2 2 2 2
??
? ? ? ? ?
? ? ? ??
? ? ? ?
? ? ? ? ??
??
2
91
v 16 6
44
??
? ? ? ?
??
??
2
v 16 6 2 4 ? ? ? ?
V = 2 m/s
4. A 34 m long ladder weighing 10 kg leans on a
frictionless wall. Its feet rest on the floor 3 m away
from the wall as shown in the figure. If F
f
and F
w
are the reaction forces of the floor and the wall,
then ratio of F
w
/F
f
will be:
(Use g = 10 m/s
2
)
(A)
6
110
(B)
3
113
(C)
3
109
(D)
2
109
Official Ans. by NTA (C)
Sol.
34m
N
2
S
3m
mg
N
1
f
?
?
2
fN
1
N mg ?
2
N sin mg cos
2
? ? ? ?
2
mg
N cot
2
??
? ?
w
2
f
2
mg
cot
F
2
F
mg
mg cot
2
?
?
??
??
??
??
2
1
4
1
cot
?
?
?
3
109
?
5. Water fall from a 40 m high dam at the rate of
?
4
9 10 kg per hour. Fifty percentage of
gravitational potential energy can be converted into
electrical energy. Using this hydroelectric energy
number of 100W lamps, that can be lit, is:
(Take g = 10 ms
-2
)
(A) 25 (B) 50
(C) 100 (D) 18
Official Ans. by NTA (B)
Sol.
4
9 10 g 40
0.5 n 100
3600
? ? ?
? ? ?
4
10 0.5
n
100
?
?
100 × 0.5 = n
n = 50
3
6. Two objects of equal masses placed at certain
distance from each other attracts each other with a
force of F. If one-third mass of one object is
transferred to the other object, then the new force
will be :
(A)
2
F
9
(B)
16
F
9
(C)
8
F
9
(D) F
Official Ans. by NTA (C)
Sol.
2
2
Gm
F
r
?
2
4m 2m
G
33
F'
r
? ? ? ?
?
? ? ? ?
? ? ? ?
?
8
F' F
9
?
7. A water drop of radius ? 1m falls in a situation
where the effect of buoyant force is negligible. Co-
efficient of viscosity of air is
??
?
52
1.8 10 Nsm and
its density is negligible as compared to that of
water
? 63
10 gm . Terminal velocity of the water
drop is:
(Take acceleration due to gravity = 10 ms
–2
)
(A)
??
?
61
145.4 10 ms (B)
??
?
61
118.0 10 ms
(C)
??
?
61
132.6 10 ms (D)
??
?
61
123.4 10 ms
Official Ans. by NTA (D)
Sol.
F = 6 rv
vt
??
4
mg
3
=
?? rg
3
v
t
3
t
4
6 rv r g
3
? ? ? ? ?
3
t
4 r g
v
3 6 r
??
??
??
3 12 3
t –5
4 r g 2 10 10 10
v
3 6 r 9 1.8 10
?
? ? ? ? ?
? ? ?
?? ??
= 123.4 × 10
–6
m/s
8. A sample of an ideal gas is taken through the
cyclic process ABCA as shown in figure. It
absorbs, 40 J of heat during the part AB, no heat
during BC and rejects 60J of heat during CA. A
work 50J is done on the gas during the part BC.
The internal energy of the gas at A is 1560J. The
work done by the gas during the part CA is:
(A) 20 J (B) 30 J
(C) –30J (D) –60 J
Official Ans. by NTA (B)
Sol.
cycle
Q 40 60 W ? ? ? ? ?
BC CA
W – 2 0J W W ? ? ? ? ?
CA BC
W – 2 0 J W ? ? ?
= –20 – (–50)
= 30 J
9. What will be the effect on the root mean square
velocity of oxygen molecules if the temperature is
doubled and oxygen molecule dissociates into
atomic oxygen?
(A) The velocity of atomic oxygen remains same
(B) The velocity of atomic oxygen doubles
(C) The velocity of atomic oxygen becomes half
(D) The velocity of atomic oxygen becomes four
times
Official Ans. by NTA (B)
4
Sol.
rms
3RT
V
M
?
T ? 2T
M
M
2
?
rms
T
V
M
?
? ? ? ? ? ?
rms rms rms
atomic molecular molecular
2
V V 2 V
1 / 2
? ? ? ?
10. Two point charges A and B of magnitude
?
??
6
8 10 C and
?
??
6
8 10 C respectively are
placed at a distance d apart. The electric field at the
middle point O between the charges is
?
?
41
6.4 10 NC . The distance ‘d’ between the point
charges A and B is:
(A) 2.0 m (B) 3.0 m
(C) 1.0 m (D) 4.0 m
Official Ans. by NTA (B)
Sol.
–q +q
O
E
–
E
+
? ?
0 2
Kq
E2
d / 2
??
0 2
Kq
E8
d
??
96
2
4
8 9 10 8 10
d
6.4 10
?
? ? ? ?
??
?
d = 3 m
11. Resistance of the wire is measured as ? 2 and ? 3
at 10°C and 30°C respectively. Temperature co–
coefficient of resistance of the material of the wire is :
(A) 0.033°C
–1
(B) –0.033°C
–1
(C) 0.011°C
–1
(D) 0.055°C
–1
Official Ans. by NTA (A)
Sol. ? ?
0
R R 1 T ? ? ? ?
? ? ? ?
0
3 R 1 3 0 – 0 ? ? ?
? ? ? ?
0
2 R 1 1 0 – 0 ? ? ?
3 1 30
2 1 10
??
?
??
1
0.033
30
? ? ?
12. The space inside a straight current carrying solenoid
is filled with a magnetic material having magnetic
susceptibility equal to
?
?
5
1.2 10 . What is fractional
increase in the magnetic field inside solenoid with
respect to air as medium inside the solenoid?
(A)
?
?
5
1.2 10 (B)
?
?
3
1.2 10
(C)
?
?
3
1.8 10 (D)
?
?
5
2.4 10
Official Ans. by NTA (A)
Sol.
5
1.2 10
?
? ? ?
5
r
1 1 1.2 10
?
? ? ? ? ? ? ?
Fractional Change
? ?
0 r 0
r
0
ni ni B
1
B ni
? ? ? ? ?
? ? ? ? ?
?
= 1.2 × 10
–5
13. Two parallel, long wires are kept 0.20 m apart in
vacuum, each carrying current of x A in the same
direction. If the force of attraction per meter of
each wire is
?
?
6
2 10 N , then the value of x is
approximately:
(A) 1 (B) 2.4
(C) 1.4 (D) 2
Official Ans. by NTA (C)
Page 5
1
FINAL JEE –MAIN EXAMINATION – JUNE, 2022
(Held On Tuesday 28
th
June, 2022) TIME : 3 : 00 PM to 6 : 00 PM
PHYSICS TEST PAPER WITH SOLUTION
SECTION-A
1. Velocity (v) and acceleration (a) in two systems of
units 1 and 2 are related as ?
21 2
n
vv
m
and
1
2
a
a
mn
? respectively. Here m and n are
constants. The relations for distance and time in
two systems respectively are:
(A)
32
1 2 1 2 3
nn
L L and T T
mm
??
(B)
42
1 2 1 2 2
nn
L L andT T
mm
??
(C)
24
1 2 1 2 2
nn
L L and T T
mm
??
(D)
24
1 2 1 2 2
nn
L L and T T
mm
??
Official Ans. by NTA (A)
Sol.
21
2
21
LL n
TT m
?
21
22
21
LL
T T mn
?
?
2
22
22
1 1
TT n
T m T mn
??
?
2
2
1
T n
mT
?
4
2
2
1
L n1
L mn m
??
3
2
3
1
L n
L m
?
2. A ball is spun with angular acceleration
? ? ?
2
6t 2t where t is in second and ? is in
rads
–2
. At t = 0, the ball has angular velocity of 10
rads
–1
and angular position of 4 rad. The most
appropriate expression for the angular position of
the ball is:
(A)
42
3
t t 10t
2
??
(B)
43
tt
10t 4
23
? ? ?
(C)
43
2t t
10t 12
36
? ? ?
(D)
3
4
t
2t 5t 4
2
? ? ?
Official Ans. by NTA (B)
Sol.
2
dw
6t 2t
dt
??
w
32
10
dw 2t t ??
?
32
w 10 2t t ? ? ?
32
d
10 2t t
dt
?
? ? ?
32
4
d 10 2t t
?
? ? ? ?
?
?
? ? ? ?
?
43
4
tt
d 10t
23
43
tt
4 10t
23
? ? ? ? ?
2
3. A block of mass 2 kg moving on a horizontal
surface with speed of 4 ms
-1
enters a rough surface
ranging from x = 0.5 m to x = 1.5 m. The retarding
force in this range of rough surface is related to
distance by F kx ?? where k = 12 Nm
-1
. The
speed of the block as it just crosses the rough
surface will be:
(A) Zero (B) 1.5 ms
-1
(C) 2.0 ms
-1
(D) 2.5 ms
-1
Official Ans. by NTA (C)
Sol.
kx 12x
a 6x
22
??
? ? ? ?
vdv
6x
dx
??
v 3/2
1 4
2
vdv 6xdx ??
??
22
22
v 4 6 3 1
2 2 2 2
??
? ? ? ? ?
? ? ? ??
? ? ? ?
? ? ? ? ??
??
2
91
v 16 6
44
??
? ? ? ?
??
??
2
v 16 6 2 4 ? ? ? ?
V = 2 m/s
4. A 34 m long ladder weighing 10 kg leans on a
frictionless wall. Its feet rest on the floor 3 m away
from the wall as shown in the figure. If F
f
and F
w
are the reaction forces of the floor and the wall,
then ratio of F
w
/F
f
will be:
(Use g = 10 m/s
2
)
(A)
6
110
(B)
3
113
(C)
3
109
(D)
2
109
Official Ans. by NTA (C)
Sol.
34m
N
2
S
3m
mg
N
1
f
?
?
2
fN
1
N mg ?
2
N sin mg cos
2
? ? ? ?
2
mg
N cot
2
??
? ?
w
2
f
2
mg
cot
F
2
F
mg
mg cot
2
?
?
??
??
??
??
2
1
4
1
cot
?
?
?
3
109
?
5. Water fall from a 40 m high dam at the rate of
?
4
9 10 kg per hour. Fifty percentage of
gravitational potential energy can be converted into
electrical energy. Using this hydroelectric energy
number of 100W lamps, that can be lit, is:
(Take g = 10 ms
-2
)
(A) 25 (B) 50
(C) 100 (D) 18
Official Ans. by NTA (B)
Sol.
4
9 10 g 40
0.5 n 100
3600
? ? ?
? ? ?
4
10 0.5
n
100
?
?
100 × 0.5 = n
n = 50
3
6. Two objects of equal masses placed at certain
distance from each other attracts each other with a
force of F. If one-third mass of one object is
transferred to the other object, then the new force
will be :
(A)
2
F
9
(B)
16
F
9
(C)
8
F
9
(D) F
Official Ans. by NTA (C)
Sol.
2
2
Gm
F
r
?
2
4m 2m
G
33
F'
r
? ? ? ?
?
? ? ? ?
? ? ? ?
?
8
F' F
9
?
7. A water drop of radius ? 1m falls in a situation
where the effect of buoyant force is negligible. Co-
efficient of viscosity of air is
??
?
52
1.8 10 Nsm and
its density is negligible as compared to that of
water
? 63
10 gm . Terminal velocity of the water
drop is:
(Take acceleration due to gravity = 10 ms
–2
)
(A)
??
?
61
145.4 10 ms (B)
??
?
61
118.0 10 ms
(C)
??
?
61
132.6 10 ms (D)
??
?
61
123.4 10 ms
Official Ans. by NTA (D)
Sol.
F = 6 rv
vt
??
4
mg
3
=
?? rg
3
v
t
3
t
4
6 rv r g
3
? ? ? ? ?
3
t
4 r g
v
3 6 r
??
??
??
3 12 3
t –5
4 r g 2 10 10 10
v
3 6 r 9 1.8 10
?
? ? ? ? ?
? ? ?
?? ??
= 123.4 × 10
–6
m/s
8. A sample of an ideal gas is taken through the
cyclic process ABCA as shown in figure. It
absorbs, 40 J of heat during the part AB, no heat
during BC and rejects 60J of heat during CA. A
work 50J is done on the gas during the part BC.
The internal energy of the gas at A is 1560J. The
work done by the gas during the part CA is:
(A) 20 J (B) 30 J
(C) –30J (D) –60 J
Official Ans. by NTA (B)
Sol.
cycle
Q 40 60 W ? ? ? ? ?
BC CA
W – 2 0J W W ? ? ? ? ?
CA BC
W – 2 0 J W ? ? ?
= –20 – (–50)
= 30 J
9. What will be the effect on the root mean square
velocity of oxygen molecules if the temperature is
doubled and oxygen molecule dissociates into
atomic oxygen?
(A) The velocity of atomic oxygen remains same
(B) The velocity of atomic oxygen doubles
(C) The velocity of atomic oxygen becomes half
(D) The velocity of atomic oxygen becomes four
times
Official Ans. by NTA (B)
4
Sol.
rms
3RT
V
M
?
T ? 2T
M
M
2
?
rms
T
V
M
?
? ? ? ? ? ?
rms rms rms
atomic molecular molecular
2
V V 2 V
1 / 2
? ? ? ?
10. Two point charges A and B of magnitude
?
??
6
8 10 C and
?
??
6
8 10 C respectively are
placed at a distance d apart. The electric field at the
middle point O between the charges is
?
?
41
6.4 10 NC . The distance ‘d’ between the point
charges A and B is:
(A) 2.0 m (B) 3.0 m
(C) 1.0 m (D) 4.0 m
Official Ans. by NTA (B)
Sol.
–q +q
O
E
–
E
+
? ?
0 2
Kq
E2
d / 2
??
0 2
Kq
E8
d
??
96
2
4
8 9 10 8 10
d
6.4 10
?
? ? ? ?
??
?
d = 3 m
11. Resistance of the wire is measured as ? 2 and ? 3
at 10°C and 30°C respectively. Temperature co–
coefficient of resistance of the material of the wire is :
(A) 0.033°C
–1
(B) –0.033°C
–1
(C) 0.011°C
–1
(D) 0.055°C
–1
Official Ans. by NTA (A)
Sol. ? ?
0
R R 1 T ? ? ? ?
? ? ? ?
0
3 R 1 3 0 – 0 ? ? ?
? ? ? ?
0
2 R 1 1 0 – 0 ? ? ?
3 1 30
2 1 10
??
?
??
1
0.033
30
? ? ?
12. The space inside a straight current carrying solenoid
is filled with a magnetic material having magnetic
susceptibility equal to
?
?
5
1.2 10 . What is fractional
increase in the magnetic field inside solenoid with
respect to air as medium inside the solenoid?
(A)
?
?
5
1.2 10 (B)
?
?
3
1.2 10
(C)
?
?
3
1.8 10 (D)
?
?
5
2.4 10
Official Ans. by NTA (A)
Sol.
5
1.2 10
?
? ? ?
5
r
1 1 1.2 10
?
? ? ? ? ? ? ?
Fractional Change
? ?
0 r 0
r
0
ni ni B
1
B ni
? ? ? ? ?
? ? ? ? ?
?
= 1.2 × 10
–5
13. Two parallel, long wires are kept 0.20 m apart in
vacuum, each carrying current of x A in the same
direction. If the force of attraction per meter of
each wire is
?
?
6
2 10 N , then the value of x is
approximately:
(A) 1 (B) 2.4
(C) 1.4 (D) 2
Official Ans. by NTA (C)
5
Sol.
Force per unit length =
?
?
0 1 2
ii
2d
??
?
??
2
0
x
2 0.2
F = 2 × 10
–6
=
?
? ? ?
??
72
4 10 x
2 0.2
??
??
2
67
x
10 10
0.2
? ? ?
2
x 10 0.2
= 2
? ? ? x 2 1.4 Amp.
14. A coil is placed in a time varying magnetic field. If
the number of turns in the coil were to be halved
and the radius of wire doubled, the electrical power
dissipated due to the current induced in the coil
would be:
(Assume the coil to be short circuited.)
(A) Halved
(B) Quadrupled
(C) The same
(D) Doubled
Official Ans. by NTA (D)
Sol. P =
2
R
?
=
2
C
dB
NA A
dt
??
?
??
??
?
P' =
2
C
NA dB
4A
2 dt
/2
??
?
??
??
?
? P' = 2P
15. An EM wave propagating in x-direction has a
wavelength of 8 mm. The electric field vibrating y-
direction has maximum magnitude of 60 Vm
–1
.
Choose the correct equations for electric and
magnetic fields if the EM wave is propagating in
vacuum :
(A)
? ?
?
???
? ? ? ?
??
??
3 8 1
y
ˆ
E 60sin 10 x 3 10 t jVm
4
? ?
???
? ? ? ?
??
??
38
z
ˆ
B 2sin 10 x 3 10 t kT
4
(B)
? ?
?
???
? ? ? ?
??
??
3 8 1
y
ˆ
E 60sin 10 x 3 10 t jVm
4
? ?
?
???
? ? ? ? ?
??
??
7 3 8
z
ˆ
B 2 10 sin 10 x 3 10 t kT
4
(C)
? ?
??
???
? ? ? ? ?
??
??
7 3 8 1
y
ˆ
E 2 10 sin 10 x 3 10 t jVm
4
? ?
???
? ? ? ?
??
??
38
z
ˆ
B 60sin 10 x 3 10 t kT
4
(D)
? ?
??
???
? ? ? ? ?
??
??
7 4 8 1
y
ˆ
E 2 10 sin 10 x 4 10 t jVm
4
? ?
???
? ? ? ?
??
??
48
z
ˆ
B 60sin 10 x 4 10 t kT
4
Official Ans. by NTA (B)
Sol.
?
? ? ? ?
?
7 0
0
8
E 60
B 2 10 T
c 3 10
? EB must be direction of propagation.
So, ? B z-axis
?
??
? ? ?
?
31
2
k 10 m
4
?
???
? ? ? ?
??
??
3 8 1
y
E 60sin 10 (x 3 10 t) j Vm
4
?
???
? ? ? ? ?
??
??
7 3 8
z
B 2 10 sin 10 (x 3 10 t) k T
4
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