Question

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.

Answer 1

Radius of pipe = 0.75 cm = 0.0075 m $[\because 1cm=\frac{1}{100}m]$
The rate of water flow = 7 m/s
$\therefore$ Length of water in 1 sec = 7 m
$\therefore$ volume of water flow in 1 hour = $Time\times Area$ $=60\times 60\times \frac{22}{7}\times 0.0075\times 0.0075\times 7$ ( $\because$ 1 hr = $=60\times 60$s)
$=3600\times 3.14\times 0.00005625\times 7=11304\times 7\times 0.00005625=79128\times 0.00005625=4.45095m^3=4.45000m^3=4450000c{m}^3=4450L$
$[\because 1000c{m}^3=1L]$