Question

If a ball is dropped from rest and falls 8 m to the ground, what is the speed just before it

Answer 1

Answer:

12.5m/s

Explanation:

(Assuming the question was asking for the speed just before it hit the ground)

We can use the first key equation of accelerated motion

Vf^2 = Vi^2+2aΔd

Vf^2 = 0 + 2(9.8)(8) (plugged in values, initial velocity is 0 since the ball was at rest)

Vf^2 = 156.8

Vf = 12.5 (squared both sides)