Question

The diameter of a wheel of a bus is 90 cm which makes 315 revolutions per minute. Determine its speed in kilometres per hour. (Take π = 22/7)

Answer 1

Diameter of wheel = 90 cm

Perimeter of wheel = 2πd

Perimeter of wheel = \(\frac{22}{7}\)x 90

Perimeter of wheel = 282.857 cm

Distance covered in 315 revolutions = 282.857× 315 = 89099.955 cm

One km = 100000 cm

Distance covered = \(\frac{89099.955}{100000}\) = 0.89 km

Speed in km per hour = 0.89 × 60 = 53.4 km per hour