Question

Question 8
Water in a canal, 6 m wide and 1.5 m deep, is flowing with a speed of 10 km/h. How much area will it irrigate in 30 minutes, if 8 cm of standing water is needed?

Answer 1

Given,

Depth of water in a canal $=1.5m$

Width$=6m$

Speed of canal $=10km/hr$ $[\because 1km=1000m]$

Length of canal in 30 min $=\frac{30}{6}\times 10=5km=5000m$

Height$=8cm=0.08m[1m=100cm]$
Volume of canal$=\text{length}\times \text{breadth}\times \text{height}$

$=1.5\times 6\times 5000=45000m^3$

$Area=\frac{Volume}{Height}$

$=\frac{45000}{0.08}=562500m^2$

Hence, area irrigated $=\frac{562500}{10000}$hectares

Area irrigated $=56.25$ hectares