Question

A rock has a mass of 25kg. The acceleration due to gravity is 10m/s2 and the height of the rock is 42m. Find the potential energy of the rock. a. 10,500j b. 5,250j

c. 220,500j d. 1,050

Answer 1

Option a is correct

Potential Energy of the rock is 10,500j.

Explanation:

Given: A rock has a mass (m) of 25 kg, the acceleration due to gravity(g) is
`10m/s^2` and the height of the rock (h) is, 42m.

Formula for potential energy depends on the force acting on the objects is P=mgh, where P is potential energy, m is mass, g is acceleration due to gravity, and h is height.

Substitute the value of m=25kg , g=
`10m/s^2` and h=42m in above formula; we have,

`P=(25kg)\cdot(10m/s^2)\cdot(42m)`

⇒
`P=10,500 kg m^2/s^2`

Using Conversion:
`1 joule(j) =kg m^2s^(-2)`

Therefore, the potential energy of the rock is, P = 10,500j