Q28 of 49 Page 1

Water running in a cylindrical pipe of inner diameter 7 cm, is collected in a container at the rate of 192.5 litres per minutes. Find the rate of flow of water in the pipe in km/h.

Given, radius of the cylindrical pipe = cm

Let the length of the cylindrical pipe be L cm


Volume of the pipe = πr2l =


= L cm3


Rate of flow in hours will be = (192.5 × 60) litres/hour


Rate of flow in cm3 will be = (192.5 × 60 × 1000) cm3/hour


Now,


⇒ 77L = (192.5 × 60 × 1000)


⸫ L = = 300000 cm = 3 km


⸫ Rate of flow of water in the pipe in 1 hour = 3 km/h


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