Question

A wheel turns with angular speed of 30 rev/s is brought to rest with constant acceleration. It turns 60 rev before it stops. Calculate its angular in rad/s²​

Answer 1

Since the angular acceleration α is constant,

0² - (30 rev/s)² = 2α (60 rev)

Solve for α :

α = -(30 rev/s)²/(120 rev) = -7.5 rev/s²

One revolution corresponds to an angular displacement of 2π radians, so

α = (-7.5 rev/s²) × (2π rad/rev) ≈ -47.12 rad/s²