A sled with a weight of 75 kg rolls down a mountain 12 m high and 80 m long

A sled with a weight of 75 kg rolls down a mountain 12 m high and 80 m long, find the speed at the end of the path with a resistance force of 80N.

Given: m (weight of the given sleigh) = 75 kg; h (mountain height) = 12 m; L (mountain length, sleigh path) = 80 m; F (drag force) = 80 N.

Constants: g (acceleration due to gravity) ≈ 10 m / s2.

To find the speed of a given sleigh at the end of the path, we apply the law of conservation of energy: Ep = Ek + Atr; m * g * h = m * V ^ 2/2 + F * S; V ^ 2 = (m * g * h – F * S) * 2 / m and V = √ ((m * g * h – F * S) * 2 / m).

Calculation: V = √ ((75 * 10 * 12 – 80 * 80) * 2/75) = 8.33 m / s.

Answer: The speed of the sleigh at the end of the path is 8.33 m / s.



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