Question 113
From a pipe of inner radius 0.75 cm, water flows at the rate of 7 m per second. Find the volume in litres of water delivered by the piper in 1 h.
Radius of pipe = 0.75 cm = 0.0075 m [∵1 cm=1100m]
The rate of water flow = 7 m/s
∴ Length of water in 1 sec = 7 m
∴ volume of water flow in 1 hour = Time× Area =60×60×227×0.0075×0.0075×7 ( ∵ 1 hr = =60×60 s)
=3600×3.14×0.00005625×7=11304×7×0.00005625=79128×0.00005625=4.45095 m3=4.45000 m3=4450000 cm3=4450 L
[∵1000 cm3=1 L]