A sled weighing 7 kg slides off a 5 m long slide with an angle of inclination of 45. What work has the force of gravity performed?

m = 7 kg.
S = 5 m.
φ = 45.
g = 9.8 m / s ^ 2.
A – ?
Mechanical work A is determined by the formula A = F * S * cos α, where F is the force under which the work is performed, S is the movement of the body, α is the angle between force and displacement.
The body is affected by the force of gravity F = m * g.
α = 90 – 45 = 45.
A = m * g * S * cos α.
A = 7 kg * 9.8 m / s ^ 2 * 5 m * cos45 = 242 J.
Answer: gravity does the work A = 242 J.