Question

A ball is shot vertically upward with a given initial velocity. It reaches a maximum height of $100$m. If on a second shot, the initial velocity is doubled then the ball will reach a maximum height of.

• A. $70.7$m
• B. $141.4$m
• C. $200$m
• D. $400$m

Answer 1

The correct option is D $400$m

Let initial velocity of ball$=$u
By $II{I}^{rd}$ equation H$=\frac{u^2}{2g}=100$m
If initial velocity is doubled
$H^{\prime }=\frac{(2u{)}^2}{2g}=\frac{4\cdot u^2}{2g}=4\times 100$
$H^{\prime }=400$m.