Question

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

Answer 1

Explanation:

Given, initial velocity of ball, u=0

Final velocity of ball, v=?

Distance through which the balls falls, s=20m

Acceleration a=10ms

−2

Time of fall, t=?

We know

v

2

−u

2

=2as

or v

2

−0=2×10×20=400 or v=20ms

−1

Now using v=u+at we have

20=0+10×t or t=2s