Question

Suppose you start an antique car by exerting a force of 460 N on its crank for 0.170 s. What angular momentum (in kg·m2/s) is given to the engine if the handle of the crank is 0.310 m from the pivot and the force is exerted to create maximum torque the entire time?

Answer 1

Torque τ = rF = (0.310 m)(460 N) = 142.6 N·m.
Angular impulse = ΔL = τΔt = 142.6 N·m × 0.170 s = 24.2 kg·m^2/s.

So the engine gains 24.2 kg·m^2/s of angular momentum.