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 pipe in 1 hour.

Answer 1

Radius of pipe = 0.75 cm = 0.0075 m   ...`[∵ 1 cm = 1/100 m]`

The rate of water flow = 7 m/s

∴ Length of water in 1 sec = 7 m

∴ Volume of water flow in 1 hour = `60 xx 60 xx 22/7 xx 0.0075 xx 0.0075 xx 7`

= 3600 × 3.14 × 0.00005625 × 7

= 11304 × 7 × 0.00005625

= 79128 × 0.00005625

= 4.45095 m³

= 4.45000 m³

= 4450000 cm³  ...[∵ 1000 cm³ = 1 L]

= 4450 L