Which statement describes the angular displacement used in calculating average angular velocity?

• A. Omega
• B. Theta
• C. Alpha
• D. L

Answer: (B)

Angular displacement is the amount of rotation an object undergoes, described by the angle θ. It is the change in angular position, Δθ, between two times. When you find average angular velocity, you divide that angular displacement by the time interval: ω̄ = Δθ/Δt. So θ is the quantity that represents the angular displacement used in the calculation. The other symbols refer to related but different ideas: ω is angular velocity (the rate of change of θ), α is angular acceleration (the rate of change of ω), and L is angular momentum. For example, if a wheel turns from θ1 to θ2 over a time Δt, the angular displacement is Δθ = θ2 − θ1, and the average angular velocity is ω̄ = Δθ/Δt.