Question 158: Motion in 1D

Question

If a ball is thrown vertically upwards with speed u, the distance covered during the last t seconds of its ascent is

Accepted Answer

Let the time taken by the ball to reach the top most point T.
$$ 	herefore $$ v = u - gT
v = 0 at top most point.
T = $${u \over g}$$
Velocity of the ball after (T - t) second
v = u - g(T - t)
= u - gT + gt = u - g$${u \over g}$$ + gt
$$ 	herefore $$ v = gt
Distance covered during the last t seconds of its ascent is
s = (gt)t - $${1 \over 2}g{t^2}$$ = $${1 \over 2}g{t^2}$$

Answer

ut

Answer

$${1 \over 2}$$ gt2

Answer

ut $$-$$ $${1 \over 2}$$ gt2

Answer

(u + gt) t.

Motion in 1D

If a ball is thrown vertically upwards with speed u, the distance covered during the last t seconds of its ascent is

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