Question

A ball is thrown vertically upward. It has a speed of $10m/sec$ when it has reached one half of its maximum height. How high does the ball rise? Take $g=10m{s}^{-2}$.

• A. $10m$
• B. $5m$
• C. $6m$
• D. $7m$

Answer 1

The correct option is A $10m$

Let consider $H=$ Maximum height

$g=-10m/s^2$

$v=0m/s$ final velocity at the maximum height

$u=$ initial velocity,

3rd equation of motion,

$v^2-u^2=2gh$

$0^2-u^2=-2gH$

$u^2=2gH$. . . . . .(1)

Now, $h=\frac{H}{2}$ and $v=10m/s$

3rd equation of motion,

$v^2-u^2=2gh$

${10}^2-2gH=-\frac{2gH}{2}$

$100=\frac{2gH}{2}$

$H=\frac{100\times 2}{2g}$

$H=\frac{100\times 2}{2\times 10}=10m$

The correct option is A.