Question

Water is being pumped out through a circular pipe whose internal diameter is 7 cm. If the flow of water is 72 cm per second, how many litres of water is being pumped out in one hour?

Answer 1

Diameter of the circular pipe = 7 cm
Radius = 7/2 cm
Rate of flow of water = 72 cm per second
Volume of water flown in 1 sec = πr2h
= 22/7 x 7/2 x 7/2 x 72
= 2772 cm3

1 cubic centimeter = 0.001 litres
2772 cm3 = 2.772 litres
Volume of water pumped in 1 sec = 2.772 litres
Volume of water pumped in 1 hour = 9979.2 litres