Question

Water flows through a cylindrical pipe, whose inner radius is 1 cm, at the rate of 80 cm/s in an empty cylindrical tank, the radius of whose base is 40 cm. What is the rise of water level in tank in half an hour?

Answer 1

Given, radius of tank, r₁ = 40 cm

Let height of water level in tank in half an hour = 1 cm.

Also, given internal radius of cylindrical pipe, r₂ = 1 cm

and speed of water = 80 cm/s i.e., in 1 water flow = 80 cm

In 30 (min) water flow = 80x 60 x 30 = 144000 cm According to the question,

Hence, the level of water in cylindrical tank rises 90 cm in half an hour.