A body weighing 100kg fell from a height of 10m onto the roof of a house, the height of which was 3m.

A body weighing 100kg fell from a height of 10m onto the roof of a house, the height of which was 3m. What is the work done by gravity?

m = 100 kg.
g = 9.8 m / s ^ 2.
h1 = 10 m.
h2 = 3 m.
A -?
According to the definition, the work of force A is determined by the formula: A = F * S * cosα. Where F is the force that performs the work, S is the displacement under the action of this force, ∠α is the angle between the force F and the displacement S.
The force of gravity is determined by the formula: F = m * g.
Move S = h1 – h2.
Since the force of gravity is directed vertically downward and the body moves vertically downward, then ∠α = 0, cos0 = 1.
A = m * g * (h1 – h2).
A = 100 kg * 9.8 m / s ^ 2 * (10 m – 3 m) = 6860 J.
Answer: gravity does the work A = 6860 J.