A bicycle's wheels are moving at a speed of 0.78 revolutions per second. The cyclist sees a log in the road and brakes, slowing the bicycle to 0.05 revolutions per second over 4 seconds. What is the angular acceleration of the bicycle wheel?

Question

Quizplus · Accepted Answer

The formula for angular acceleration (α) is: α = Δω/Δt Where: Δω is the change in angular velocity (expressed in revolutions per second - rev/s) Δt is the change in time (expressed in seconds) Δω = ω₂ - ω₁ Δt = t₂ - t₁ Solve for angular acceleration: α = (0.05 rev/s - 0.78 rev/s) / 4 s α = - 0.73 rev/s / 4 s α = - 0.18 rev/s² The negative sign indicates the rate has slowed because the cyclist has braked.

A Bicycle's Wheels Are Moving at a Speed of 0