We'll use the equation:

$\overline{){{\mathbf{\omega}}}_{{\mathbf{f}}}{\mathbf{=}}{{\mathbf{\omega}}}_{{\mathbf{0}}}{\mathbf{+}}{\mathbf{\alpha}}{\mathbf{t}}}$

We'll also use the equation:

$\overline{){{{\mathbf{\omega}}}_{{\mathbf{f}}}}^{{\mathbf{2}}}{\mathbf{=}}{{{\mathbf{\omega}}}_{{\mathbf{0}}}}^{{\mathbf{2}}}{\mathbf{+}}{\mathbf{2}}{\mathbf{\alpha \theta}}}$

**A)**

Solve for α, from the first equation and get:

α = (ω_{f} - ω_{t})/t

As you finish listening to your favorite compact disc (CD), the CD in the player slows down to a stop. Assume that the CD spins down with a constant angular acceleration. A) If the CD rotates clockwise (let's take clockwise rotation as positive) at 500rpm (revolutions per minute) while the last song is playing, and then spins down to zero angular speed in 2.60s with constant angular acceleration, what is alpha_vec, the angular acceleration of the CD, as it spins to a stop? B)How many revolutions does the CD make as it spins to a stop?

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Our tutors have indicated that to solve this problem you will need to apply the Rotational Velocity & Acceleration concept. You can view video lessons to learn Rotational Velocity & Acceleration. Or if you need more Rotational Velocity & Acceleration practice, you can also practice Rotational Velocity & Acceleration practice problems.