Question

A flywheel slows down uniformly from 1200 rpm to 600 rpm in 5 s. Find the number of revolutions made by the wheel in 5 s.

Answer 1

Data : ω₀ = 1200 rpm, ω = 600 rpm, f = 5 s 

Since the flywheel slows down uniformly, its angular acceleration is constant. Then, its average angular speed,

Its angular displacement in time t,

θ = ω_av .t = 15 × 5 = 75 revolutions