Question

Question 18

Answer 1

Answer:

5.5 kg

Explanation:

The gravitational potential energy of an object is given by

$U=mgh$

where

m is its mass

g is the acceleration of gravity

h is the height of the object above the ground

For the rock in the problem, we know:

h = 12 m is the height above the ground

U = 650 J

g = 9.8 m/s^2

Therefore, we can solve the equation for m, the mass of the rock:

$m=\frac{U}{gh}=\frac{650}{(9.8)(12)}=5.5 kg$