Question

A ball is gently dropped from a height of 20 m. If its velocity increases uniformly at the rate of 10ms-2 , with what velocity will it strike the ground? After what time will it strike the ground?

August 25, 2024

Answer

Here, u = 0 m/s, s = 20 m, a = 10 ms^-2 ,

v = ?,

t = ?

Using v² – u² = 2as

We have, v² – 0² = 2 × 10 × 20 = 400 ⇒ v = 20 ms^-1 .

and t = (v – u) ÷ a = 20 ÷ 10 = 2 s

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