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i) v2 = u2 - 2as
but v = 0
u2 = 2gs = 2 x 10 x 100 = 2000 m/s,
u = $\sqrt2000 = 44.72m/s$
ii) s = ut - $\frac{1}{2}gt^2$ but s = 0,
t = $\frac{2u}{g}$ = $\frac{2\times 44.72}{10}$
= 8.944s
johnmulu answered the question on February 14, 2017 at 05:37
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