A 16kg stone falls 40m. Find the stone's kinetic energy just before it strikes the ground.

Answer 1

velocity when stone hits the ground

v = √2as

KE = 1/2 mv^2 = 1/2 m * 2as = m*a*s
= 16 * 9.8 * 40 = 6272kg-m/s^2(N)