Question

A body projected vertically upwards with a velocity of $19.6m{s}^{-1}$ reaches a height of $19.6m$ on earth. If it is projected vertically up with the same velocity on moon, then the maximum height reached by it is ($g_{earth}=gm{s}^{-2}$, $g_{moon}=\frac{g}{6}m{s}^{-2}$)

• A. 19.18 m
• B. 3.3 m
• C. 9.9 m
• D. 117.6 m

Answer 1

Answer: (D)

117.6 m

$v^2=u^2-2gs\Rightarrow s=\frac{u^2}{2g}$
$v=0$ for maximum height.
On moon, $g^{\prime }=\frac{g}{6}$
Hence $s^{\prime }=\frac{s}{\frac{1}{6}}=6s=6\times 19.6=117.6m$