a body of mass 2kg is lifted up to a height of 10m an then allowed to fall . find the potential and kinetic enrgy that it has just before touching the ground .
2 persons , a and b each weighing 50 kg start climbing up a rope separately . a takes 20s while b takes 25s to reach a height of 8m . what is the work done by each ? who has done more work in 1s ? name the term used for work done in unit time ?
how is watt related to joules ?
the power of motor pump is 2 kW. how much water per minute the pump can raise to a height of 6m .
Answers
Answered by
0
1. Potential energy of the body at height h is = mgh
Potential energy before touching the ground is = mgx0 = zero.
From the law of conservation of energy,
Potential energy at the top = Kinetic energy before touching the ground.
K,E = mgh = 2x10x9.8 = 196 J
2. Work done against the gravitational force by both the persons is same = mgh
Both have different power.
Work done per unit tine is known as power.
Due to paucity of time it would not be possible for us to provide the answers to all your queries. Try solving rest of the questions yourself and if you face any difficulty then do get back to us.
Potential energy before touching the ground is = mgx0 = zero.
From the law of conservation of energy,
Potential energy at the top = Kinetic energy before touching the ground.
K,E = mgh = 2x10x9.8 = 196 J
2. Work done against the gravitational force by both the persons is same = mgh
Both have different power.
Work done per unit tine is known as power.
Due to paucity of time it would not be possible for us to provide the answers to all your queries. Try solving rest of the questions yourself and if you face any difficulty then do get back to us.
Similar questions