Question

A rock falls off a cliff that is 82 m high. How fast is the rock moving when it hits the ground?

Answer 1

40.1m/s

Step-by-step explanation:

This is a kinematics problem

x = 82m

a = -9.8m/s^2

v(initial) = 0

Find: v(final)

Using kinematics equation:

vf^2 = vi^2 + 2a(delta)x

vf^2 = 0 + 2*(-9.8)*(82)

vf = sqrt(1607.2) = 40.09m/s

The is traveling with a velocity of 40.1m/s when it hits the ground.