# physics

A compact disc (CD), initially at rest, reaches an angular speed of 40 rad/s in 5.0 s.
a. What is the magnitude of its angular acceleration?
b. How many revolutions does the CD make in 5.0 s?

1. 0
2. 0
1. a. acceleration = speed / time ... 40 / 5.0

b. (average speed) * time
...[(0 + 40)/2] * 5.0

1. 0
posted by Scott

1. 0
posted by Henry

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