Q40 of 56 Page 13

A hemispherical tank, full of water, is emptied by a pipe at the rate of 25/7 liters per sec. How much time will it take to empty half the tank if the diameter of the base of the base of the tank is 3 m? (CBSE 2012)

1000 liters = 1 m3


1 liters = 1/1000 m3



Required time


Volume of hemisphere = 2/3πr3




= 990 seconds


= 16 mins. 30 secs.

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