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A parachutist after bailing out falls 52...

A parachutist after bailing out falls 52 m without friction. When the parachute opens, she decelerates at `2.1 ms^(-2)` & reaches the ground with a speed of `2.9 ms^(-1)`.
(i) How long has been the parachutist in the air? (ii) At what height did the fall begin?

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The correct Answer is:
(i) 17.1 s (ii) 293.8 m
(i)
`2.1=(32-2.9)/t, t=29/2.1 cong 14 :. 14+3.3 cong 17`
(ii) Height `=52+1/2 [32+2.9]xx14=293.8`
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