Question

A stone is dropped from a height  h. It hits the ground with a certain momentum P. If the same stone is dropped from a height 100% more than the previous height, the momentum when it hits the ground will change by

(a) 68%

(b) 41%

(c) 200%

(d) 100%

Answer 1

Correct option  (b) 41%

Explanation:

When a stone is dropped from a height h, it hits the ground with a momentum

P = m√2gh  ...(i)

where m is the mass of the stone.When the same stone is dropped from a height 2h(i.e. 100% of initial), then its momentum with which it hits the ground becomes