Question Detail
Question
A flywheel's rotation rate increases from 6 rev/s to 12 rev/s in 8 seconds. What is its angular acceleration in rad/s²?
Correct Answer
Option B is the correct answer.
Detailed Explanation
Initial ωi = 6 rev/s * 2π rad/rev = 12π rad/s. Final ωf = 12 rev/s * 2π rad/rev = 24π rad/s. Using α = (ωf - ωi)/t = (24π - 12π) rad/s / 8 s = (12π)/8 = 1.5π rad/s² ≈ 4.71 rad/s².
Hint
First convert the angular velocities from rev/s to rad/s. Then apply the formula for angular acceleration.