Work Done by Gravity Formula

Work Done by Gravity Formulas - Gravitational Force

Force due to gravity acts in downward direction. So for a freely falling object work done by force due to gravity is given by:
W = mgh
Where, W = work done
g = acceleration due to gravity
h = height of free fall
If the angle between gravitational force and direction of motion is 𝚹, then work done due to gravity is given by
W = mgh cos 𝚹

So if an object is moving in horizontal direction on the surface of earth, then work done by gravity is ‘zero’.

Example:
A 5 kg box falls at angle 450 from a height of 10√2 m. Determine the work done by gravity.
Solution:
Given:
Mass m = 10 kg,
angle = 450
The work done by gravity formula is given by,
W = mgh cos θ
W = 5 × 9.8 × 10√2 cos 450
= 490 J
Therefore, the work done by gravity is 490 J.

Question:
If work done by gravity on a freely falling object of mass 4Kg is 1000J, Find the height from which it’s falling.