Question

During the time a compact disc (CD) accelerates from rest to a constant rotational speed of 477 rev/min, it accelerates with an angular acceleration of 794 rad/s2 . What is the angular displacement of the CD?

answer is pi/2 rad

Answer 1

Given: Initial angular velocity = $\omega _{i}$ = 0.

Final angular velocity =
w2T X frequency
=  
2T x 477 60
rad/s.

angular acceleration = $\alpha$= 794 rad/s².

Angular displacement is to be calculated, i.e $\theta$.

As the angular acceleration is constant, we can apply .

w2ab

Therefore
3
= $\frac{\pi }{2}$ rad.