Question

The length of the minute hand of a clock is 21 cm. What is the area swept by the minute hand between 3: 20 and 3: 40?

Answer 1

When the minute hand moves from 3:20 to 3:40, the angle it covers is ${120}^{\circ }$ since the minute hand moves 6° per minute

$\therefore$ Required area $=(\frac{120}{360}\times \frac{22}{7}\times 21\times 21)c{m}^2=462c{m}^2$ (1 mark)