Finding Angular Speed

A water wheel, shown in Figure 24, completes 1 rotation every 5 seconds. Find the angular speed in radians per second.

Figure 24

Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.

Solution
The wheel completes 1 rotation, or passes through an angle of $2 π$ radians in 5 seconds, so the angular speed would be $ω = \frac{2 π}{5} \approx 1.257$ radians per second.

Your turn

The book's Try It right after this example: same idea, new numbers. Only the answer is given.

An old vinyl record is played on a turntable rotating clockwise at a rate of 45 rotations per minute. Find the angular speed in radians per second.

How did it go?