The ball's return velocity is (-20 m/s) before reaching its starting location.
According to the 3rd equation of motion-
An object that is falling freely has a starting velocity of "0"
The object accelerates at a rate of "g."
Let 'h' represent the distance the item travels while in free fall.
We can now get the ultimate velocity of the object shortly before it touches the earth with this equation,
v²=u²+2as
Calculation-
For upward motion,
providing that,
The ball's initial speed is u = +20 m/s.
So, v²= u² + 2as
⇒0= (20)² - 2gH [ where 'H' = maximum height reached]
⇒H= 400/2g
For downward motion,
v²=u²+2as
⇒v²= 0²+2g*400/2g
⇒v²= 400 m/s
⇒v= 20 m/s
Therefore, the ball's return velocity is (-20 m/s) before reaching its starting location.
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