A trolleybus weighing 10 tons, moving away, gained 10 m / s on the way. Find the drag coefficient

A trolleybus weighing 10 tons, moving away, gained 10 m / s on the way. Find the drag coefficient if the traction force is 14 kN.

Data: m (mass) = 10 t (10 * 10 ^ 3 kg); the trolleybus was moving from a standstill (V0 (initial speed) = 0 m / s); S (path) = 50 m; V (speed acquired by the trolleybus) = 10 m / s; F (pulling force) = 14 kN (14 * 10 ^ 3 N).

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

We express the resistance coefficient from the formula: m * a = m * V ^ 2 / 2S = F – Fcopr = F – μ * m * g; μ * m * g = F – m * V ^ 2 / 2S and μ = (F – m * V ^ 2 / 2S) / (m * g).

Calculation: μ = (14 * 10 ^ 3 – 10 * 10 ^ 3 * 10 ^ 2 / (2 * 50)) / (10 * 10 ^ 3 * 10) = 0.04.