A compact disk (CD) speeds up uniformly from rest to 310 rpm in 3.3s. (a) descri
ID: 1475527 • Letter: A
Question
A compact disk (CD) speeds up uniformly from rest to 310 rpm in 3.3s. (a) describe a strategy that allows you to calculate the number of revolutions the CD makes in this time. (b) use your strategy to find the number of revolutions. A compact disk (CD) speeds up uniformly from rest to 310 rpm in 3.3s. (a) describe a strategy that allows you to calculate the number of revolutions the CD makes in this time. (b) use your strategy to find the number of revolutions. A compact disk (CD) speeds up uniformly from rest to 310 rpm in 3.3s. (a) describe a strategy that allows you to calculate the number of revolutions the CD makes in this time. (b) use your strategy to find the number of revolutions.Explanation / Answer
A. Use the kinematic equations for rotation to find the average angular speed during the time interval and then the angle through which the disk spins during this interval.
Find the average angular speed over the time interval and find d(theta).
B. d(theta) = 0.5*(w + w0)*t
= 0.5*(310 + 0)*(3.3/60) = 8.525 rev