A stone is dropped from a height $h$. It hits the ground with a certain momentum $P$. If the same st

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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 $300 \%$ more than the previous height, the momentum when it hits the ground will change by\

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(b) : When a stone is dropped from a height $h$, it hits the ground with a momentum $P=m \sqrt{2 g h}$\ where $m$ is the mass of the stone.\ When the same stone is dropped from a height $4 h$ (i.e. $400 \%$ of initial as it is 300% more), then its momentum with which it hits the ground becomes $P^{\prime}=m \sqrt{2 g(4 h)}=2 P \quad$ (Using (i))\ $\%$ change in momentum $=\frac{P^{\prime}-P}{P} 	imes 100 \%$ $$ =\frac{2 P-P}{P} 	imes 100 \%=100 \% $$