Question

A certain CD has a playing time of 76 minutes. When the music starts, the CD is rotating at an angular speed of 4.10 × 10 2 4.10×102 revolutions per minute (rpm). At the end of the music, the CD is rotating at 2.90 × 10 2 2.90×102 rpm. Find the magnitude of the average angular acceleration of the CD. Express your answer in rad/s².

Answer 1

average acceleration = 2.74 x 10⁻³ rad/s²

Step-by-step explanation:

given,

CD playing time = 76 minutes

initial angular speed of CD = 4.10 × 10² rev/min

=
`4.1 * 10^2* (2 \pi)/(60)`

= 42.9 rad/s

final angular speed of CD = 2.90 × 10² rev/min

=
`2.9 * 10^2* (2 \pi)/(60)`

= 30.37 rad/s

average acceleration =
`(\omega_f-\omega_i)/(t)`

=
`(30.37 -42.9)/(76* 60)`

average acceleration = 0.00274 rad/s²

average acceleration = 2.74 x 10⁻³ rad/s²