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Question
The troops (soldiers) equipped to be dropped by parachutes from an aircraft are called paratroopers. Why do paratroopers roll on landing ?
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Solution
When a parachutist lands on the ground, the momentum he has is high enough to hurt him on hitting the ground. Rolling on the ground just after landing will convert the kinetic energy of fall into rotational energy which will be dissipated gradually by the friction of the ground. Thus, the parachutist will have a safe landing if he rolls on landing.
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