Question

g A CD is spinning on a CD player. You open the CD player to change out the disk and notice that the CD comes to rest after 15 revolutions with a constant deceleration of 120 r a d s 2 . What was the initial angular speed of the CD

Answer 1

Answer:

$\omega_1=150rads/sec$

Explanation:

From the question we are told that:

Number of Revolution $N=15=30\pi$

Deceleration $d= -120 rads/2$

Generally the equation for  initial angular speed $\omega_1$ is mathematically given by

 $\omega_2^2=\omega_1^2 +2(d)(N)$

 $0=\omega_1^2 +2(-120)(20 \pi)$

 $\omega_1^2=7200 \pi$

 $\omega_1=150rads/sec$