Question

The minute hand of a watch is 1.5 cm long. How far does its tip move in 40 minutes? (Use π = 3.14).

Answer 1

Solution: In 60 minutes, the minute hand of a watch completes one revolution. Therefore,
in 40 minutes, the minute hand turns through 2/3 of a revolution. Therefore,
θ = 2 × 360°/3
or 4π/3
radian. Hence, the required distance travelled is given by
l = r θ = 1.5 × 4π/3 cm = 2π cm = 2 × 3.14 cm = 6.28 cm.