Q5 of 48 Page 270

A hemispherical tank of radius 2.4 m is full of water. It is connected with a pipe which empties it at the rate of 7 litres per second. How much time will it take to empty the tank completely?

Given.


A hemispherical tank of radius 2.4 m is full of water


Rate of water flow is 7 litres per second


Formula used/Theory.


Volume of hemisphere = πr3


Volume of hemispherical bowl = πr3


= × (2.4 m)3


= 28.96m3


1m3 = 1000 litres


28.96m3 = 28.964 × 1000 litres


= 28964 litres


Rate of flow is 7 litres in 1 second


Rate of flow is 1 litres in second


Rate of flow is 28964 litres in second


Is 4137.8 seconds


In minutes = = 68.96 minutes


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