A body is displaced from (0, 0) to (1m, 1m) along the path x=y by a force . The work done by this force will be :
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2.
3.
4.
A block of mass m initially at rest, is dropped from a height h onto a spring of force constant k. If the maximum compression in the spring is x, then:
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2.
3.
4.
A block of mass \(M\) moving on the frictionless horizontal surface collides with the spring of spring constant \(k\) and compresses it by length \(L.\) The maximum momentum of the block after the collision will be:
1. | zero | 2. | \(ML^2 \over k\) |
3. | \(\sqrt{Mk}L\) | 4. | \(kL^2 \over 2M\) |
A body of mass m accelerates uniformly from rest to v1 in time t1. As a function of time t, the instantaneous power delivered to the body will be:
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4.
A body of mass 1 kg is thrown upwards with a velocity of It momentarily comes to rest after attaining a height of 18 m. How much energy is lost due to air friction?
1. 20 J
2. 30 J
3. 40 J
4. 10 J
1. | no work is done by the tangential force. |
2. | no work is done by the centripetal force. |
3. | work done by the tangential force is always positive. |
4. | work done by the centripetal force is negative. |
Two springs of spring constants k and 3k are stretched separately by the same force. The ratio of potential energy stored in them respectively, will be:
1. | 3: 1 | 2. | 9: 1 |
3. | 1: 3 | 4. | 1: 9 |
Mark the correct statement(s):
1. Internal forces cannot increase the kinetic energy of a system.
2. Internal forces may increase the kinetic energy of a system.
3. Work done by kinetic friction is always negative.
4. Both (2) & (3)
A bullet fired towards a wall reduces its kinetic energy by half after the penetration of 6 cm. The further penetration of the bullet into the wall is:
1. 2 cm
2. 1 cm
3. 6 cm
4. 3 cm
A body having an initial kinetic energy 2 J collides with an identical body at rest. The maximum loss of kinetic energy in the collision will be:
1. | 2 J | 2. | Zero |
3. | 1 J | 4. | 1.5 J |