a 10k rock is dropped from a height of 20m and hits the ground below at a speed of 60m/s. Calculate the gravitational potential energy before it was dropped

1960 Joules

Step-by-step explanation:

The formula for Gravitational Potential Energy (GPE) is:

GPE = mgh

Where

m is the mass in kg

g is the gravitational field strength (in earth, it is 9.8)

h is the height in meters

In the questions, it is given

mass = 10 kg

height = 20 m

g = 9.8

Substituting, we get:

GPE = mgh

GPE = (10) (9.8) (20) = 1960 Joules