Question

A stone is thrown straight upward and reaches a maximum height of 32.3 m above itslaunch point. What was the initial speed with which the stone was thrown upwards?Answer:m/s

Answer 1

Answer:

The initial speed = 25.16 m/s

Explanation:

The maximum height, H = 32.3 m

The initial speed, u = ?

The formula for the maximum height of a projectile is:

$H=\frac{u^2}{2g}$

Substitute H = 32.3m and g = 9.8 m/s² into the formula and solve for u

$\begin{gathered} 32.3=\frac{u^2}{2(9.8)} \\ \\ u^2=32.3(2)(9.8) \\ \\ u^2=633.08 \\ \\ u=\sqrt{633.08} \\ \\ u=25.16\text{ m/s} \end{gathered}$

The initial speed = 25.16 m/s