Question

A stone is released from a height of 10 m. Its potential energy at the highest point is 1000 J.
Find the following: (Take g = 10 m/s²)
i.
ii.
Its potential energy at height 5 m from the ground
Its kinetic energy at a height of 5 m from the ground
The sum of kinetic and potential energies at a height of 5 m from the ground
The kinetic energy just before impact
iii.
iv.
V.
Compare the final answer values of (iii) and (iv) and state which law is
responsible for the observation.​

Answer 1

According to the conversation of energy

total potential energy + Kinetic energy = total mechanical energy (remains constant)

so, potential energy at 5m from ground = 500J

since the stone came halfway

and total machanical energy = 1000J (initially K.E = 0,P.E = 1000J)

Kinetic energy at 5m = 500 (1000-500)