Question

The minute hand of a clock is $5$cm long.How far does the tip of the hand move in $15$ minutes?

Answer 1

The minute hand moves through $2\pi \times \frac{15}{60}=\frac{\pi }{2}$ radians.

Since the length of the minute hand is $5$cm, the distance moved by the tip of the hand is given by the formula,$l=r\theta =5\times \frac{\pi }{2}=\frac{5\pi }{2}$cm