Question

A body of mass 20 kg is lifted up by 10 m . calculate it's potential energy .lf this body is allowed to fall, find its kinetic energy

Answer 1

Potential energy = mgh

Taking g as 10m/s²,

So potential energy = 20 × 10 × 10

=> potential energy = 2000 Joules.



We have to find its kinetic energy at the final velocity.

v² - u² = 2gh

=> v² - 0 = 2× 10 × 10

=> v² = 200

Now kinetic energy = 1/2 × m × v²

=> kinetic energy = 1/2 × 20 × 200

=> kinetic energy = 2000 Joules

Answer 2

kinetic energy =2000j