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Pragati Gupta
Subject: Physics
, asked on 6/1/18
A cart of mass
m
travelling on a horizontal track with speed
v
, collides with a stationary cart of mass 2
m
. The
can
stick together. The impulse exerted by one cart on the other has magnitude:
(A) 0 (B) 2
mv
/3 (C)
mv
(D) 3
mv
/2
Answer
1
Pragati Gupta
Subject: Physics
, asked on 6/1/18
A 640-N hunter gets a rope around a 3200-N polar bear. They are stationary, 20 m apart, on frictionless level
a
. When the hunter pulls the polar bear to him, the polar bear will move:
(A) 1.0 m (B) 3.3 m (C) 10 m (D) 12 m
Answer
1
Pragati Gupta
Subject: Physics
, asked on 6/1/18
Solve 21
21. The first graph shows the potential energy
U
(x) for a particle moving on the x axis. Which of the other four graphs correctly gives the force
F
exerted on the particle?
Answer
1
Pragati Gupta
Subject: Physics
, asked on 2/1/18
Q. A block attached to the end of ideal and moved from coordinate
x
i
to coordinate
x
f
. The relaxed
position is at x = O. The work done by spring is positive if:
A.
x
i
= 2 cm and
x
f
= 4 cm
B.
x
i
= 2 cm and
x
f
= 4 cm
C.
x
i
= -2 cm and
x
f
= -2 cm
D.
x
i
= -4 cm and
x
f
= -2 cm
Answer
1
Tulsi Mehta
Subject: Physics
, asked on 29/12/17
a ball is dropped from a height of 10 m. if coefficient of restitution is 0.4 , then find height to which ball rebounds
Answer
2
Tulsi Mehta
Subject: Physics
, asked on 29/12/17
In elastic collision , do the bodies stick to each othwr after collision ?
Answer
1
Tulsi Mehta
Subject: Physics
, asked on 29/12/17
Answer isC
2 identical balls of each of 4 kg are moving towards each other with speeds 2 m/s and 3 m/s respectively. they undergo head on perfectly elastic collision. impulse imparted by one ball on other is
A. 12 Ns
B. 8Ns
C.20Ns
D.40 Ns
Answer
2
Tulsi Mehta
Subject: Physics
, asked on 29/12/17
30. Two ivory balls are placed together at rest. A third identical ball moving with velocity u in line of first two balls; as shown in figure collide head on elastically then
(I) Third ball comes to rest with second ball While first ball moves with speed u
(2) Third ball comes to rest and other two move together with speed u/2
(3) All three ball move together with speed u/3
(4) All three ball move in such a manner each makes angle 120 degree to each other
Answer
1
Tulsi Mehta
Subject: Physics
, asked on 29/12/17
Answer -4
2 balls of mass m each undergo oblique collision. if collision is perfectly elastic , then angle between there velocities after collision is
A. Pi/4
B.pi/3
C.pi/6
D.pi/2
Answer
1
Tulsi Mehta
Subject: Physics
, asked on 29/12/17
Answer-D
a heavy vehicle moving with velocity =15m/s strikes an object of very small mass at rest head on elastically. velocity of object after collision is
A.15 m/s
B.25 m/s
C.20 m/s
D.30 m/s
Answer
2
Tulsi Mehta
Subject: Physics
, asked on 29/12/17
Q22
Q22. A ball of mass m is released from the top of an inclined plane of inclination
θ
as shown. It strikes a rigid surface at a distances
3
l
4
from top elastically. Impulse imparted to ball by the rigid surface is
1
m
3
2
gh
2
m
3
gh
3
2
m
3
gh
4
m
6
gh
Answer
1
Tulsi Mehta
Subject: Physics
, asked on 29/12/17
Q. Explain last step
Answer
1
Tulsi Mehta
Subject: Physics
, asked on 28/12/17
If a simple pendulum of length I and mass m has maximum angular displacement theta, then find its maximum kinetic energy.
(Answer = mgl(1- cos theta) )
Answer
1
Tulsi Mehta
Subject: Physics
, asked on 28/12/17
The potential energy of a particle of mass 1 kg moving along x axis is given by U(x) =[ (x^2/2)-x ] Joules .If total mechanical energy of particle is 2 J, then find its maximum speed.
(Answer - root 5 m/s)
Answer
1
Tulsi Mehta
Subject: Physics
, asked on 28/12/17
determine a unit vector perpendicular to vector a=2i +3 j+4 k?
(Answer: i +2j -2k)
Answer
1
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Next
What are you looking for?
(A) 0 (B) 2mv/3 (C) mv (D) 3mv/2
(A) 1.0 m (B) 3.3 m (C) 10 m (D) 12 m
21. The first graph shows the potential energy U (x) for a particle moving on the x axis. Which of the other four graphs correctly gives the force F exerted on the particle?
position is at x = O. The work done by spring is positive if:
A. = 2 cm and = 4 cm
B. = 2 cm and = 4 cm
C. = -2 cm and = -2 cm
D. = -4 cm and = -2 cm
2 identical balls of each of 4 kg are moving towards each other with speeds 2 m/s and 3 m/s respectively. they undergo head on perfectly elastic collision. impulse imparted by one ball on other is
A. 12 Ns
B. 8Ns
C.20Ns
D.40 Ns
30. Two ivory balls are placed together at rest. A third identical ball moving with velocity u in line of first two balls; as shown in figure collide head on elastically then
(I) Third ball comes to rest with second ball While first ball moves with speed u
(2) Third ball comes to rest and other two move together with speed u/2
(3) All three ball move together with speed u/3
(4) All three ball move in such a manner each makes angle 120 degree to each other
2 balls of mass m each undergo oblique collision. if collision is perfectly elastic , then angle between there velocities after collision is
A. Pi/4
B.pi/3
C.pi/6
D.pi/2
a heavy vehicle moving with velocity =15m/s strikes an object of very small mass at rest head on elastically. velocity of object after collision is
A.15 m/s
B.25 m/s
C.20 m/s
D.30 m/s
Q22. A ball of mass m is released from the top of an inclined plane of inclination as shown. It strikes a rigid surface at a distances from top elastically. Impulse imparted to ball by the rigid surface is
(Answer = mgl(1- cos theta) )
(Answer - root 5 m/s)
(Answer: i +2j -2k)