Question

The area of cross section of a pipe is 5.4 square cm and water is pumped out of it at the rate of 27 km per hour. Find, in litres, the volume of water which flows out of the pipe in 2 minutes.

Answer 1

1km/hr

= `(1"km")/(1"hr")`

= `(100000"cm")/(3600"s")`

= `(250)/(9)`cm/s
Rate of flow of water
= Area of cross section x rate
= 5.4 x 27km/hr
= 5.4 x 27 x 250/9 cm/s
= 4050 cm³/s
Volume of water flown out in 2minutes
= Rate of flow of water x Time
= 4050 x (2 x 60 seconds)
= 486000cm³

= `(486000)/(1000)`
= 486litres    ...(∵ 1litre = 1000cm³)
∴ Volume of water which flows out of the pipe in 2minutes is 486litres.