Question

The diameter of the wheels of a bus is 140cm .How many revolutions per minute must a wheel make in order to move at a speed of 66km per hour?​

Answer 1

answer

diameter=140cm

radius=140/2=70cm=70/100m=0.7m

1hour=66km

60minute=66ooom(1km=1000m)

1minute=66000/60

1minute=1100m

distance=no. of revolution ×circumference of wheel

1100= no. of revolution×2×22/7×0.7

1100=no. of revolution×4.4

no. of revolution=1100/4.4=250