Question

Calculate the potential energy of a stone weighing 2.5 kg placed at a height of 6 m.
Calculate the work done by a boy in lifting a 10 kg laptop from the ground and keeping it on a
5
6. A person does 5000 J of work in climbing a tree of height 5 m. Calculate the mass of the person.
7. A 900 kg compact car is moving at a certain speed. If its kinetic energy is 3,20,000 ), find the
velocity at which the car is travelling.
8. Two bodies of equal masses move with uniform velocities v and 3v, respectively. Find the ratio o
their kinetic energies.​

Answer 1

Explanation:

1). mass =2.5 kg

height=6m

g=9.8m/s

potential energy=mgh

2.5 ×6×9.8=147kj