The minute hand of a clock is 3cm long, then the distance covered by the tip in 20 minutes is

Length of minute hand of a clock  $=3$ cm

Angle made by the tip in  20 min $=20\times 6$

$=120°$

Distance covered by the tip in 20 min

$=\frac{x}{360}2\pi r$

$=\frac{120}{360}\times \frac{22}{7}\times 3\times 2$

$=\frac{44}{7}$  mts