State the work-energy theorem.
Work, Energy and Power
Original Khojo Papers practice question — not from a past board paper.
A conservative force is one for which the work done in moving a body between two points is independent of the path taken, and the work done round any closed path is zero. Gravitational and elastic forces are examples. A potential energy can be defined for such a force, which cannot be done for friction.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Friction and viscous drag are non-conservative.
From the same topic and chapter, at a similar level.
State the work-energy theorem.
Work, Energy and Power
A body of mass 2 kg falls freely from rest through 20 m. Find its kinetic energy on reaching the ground and its momentum. Take g = 10 m s−2.
Work, Energy and Power
A force of 50 N acts on a body and moves it 4 m at 60° to the direction of the force. Find the work done.
Work, Energy and Power
A pump lifts 600 kg of water through 10 m in 30 s. Find its power. Take g = 10 m s−2.
Work, Energy and Power
Distinguish between elastic and inelastic collisions.
Work, Energy and Power
A body of mass 4 kg moving at 6 m s−1 collides head-on with a stationary body of mass 2 kg and they move off together. Find their common velocity.
Work, Energy and Power