Find Angular Velocity when given Angular Acceleration?

[Justinclewis94]

Homework Statement

Starting from rest, a spinning compact disk undergoes an angular acceleration of 5.0 rad/s^2. What is the angular speed of the disk after 3 revolutions?

Homework Equations

a=Δω/Δt
ω=Δθ/Δt

The Attempt at a Solution

I do not understand how to solve this equation when I am not given a time. I don't have a radius, so I can't find the circumference either. How can I solve this?

 

[DrClaude]

Thread locked pending moderation.