Question

A $5kg$ ball is thrown upwards at a speed of $10m{s}^{-1}$. Assume $g$= $10m{s}^{-2}$

1. Calculate the maximum height attained by it.
2. Find the potential energy when it reaches the highest point.

Answer 1

Step 1: Given data

Mass of ball $\left(m\right)$ =$5kg$

The velocity of the ball $\left(v\right)$ $=10m{s}^{-1}$

Acceleration due to gravity $\left(g\right)$ $=10m{s}^{-2}$

Step 2: Calculating the maximum height attained

For maximum height, we know

$v^2-u^2$ = $2gs$, where $u$ is the initial velocity, $g$is the acceleration, and $s$is the distance or height attained

$v^2$ = $u^2+2gs$

Here, $u$ = $0$

On applying the values,

${10}^2$ = $2\times 10\times s$

$s$ = $\frac{100}{20}$= $5m$

Hence, the maximum height attained by the ball is $5m$.

Step 3: Calculating the Potential energy

For potential energy $(P.E)$,

$(P.E)$ = $m\times g\times h$

$(P.E)$ = $5\times 10\times 5$= $250J$

Hence the Potential energy when it reaches the highest point is $250J$.