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

## Given

It is given that the canal is the shape of a cuboid with dimensions as:

Height (h) = 1.5 m

The speed of canal = 10 km/hr

Length of canal covered in 1 hour = 10 km

## Find out

We need to find how much area will it irrigate in 30 minutes if 8cm of standing water is desired

## Solution

Length of canal covered in 60 minutes = 10 km

Length of canal covered in 1 min = (1/60)x10 km

Length of canal covered in 30 min (l) = (30/60)x10 = 5km = 5000 m

We know that the canal is cuboidal in shape.

## Formula

Volume of cuboid= l x b x h

Since canal is cuboidal shape

Volume of canal = lxbxh

= 5000x6x1.5 m3

= 45000 m3

Now,

Volume of water in canal = Volume of area irrigated

= Area irrigated x Height

So, Area irrigated = 56.25 hectares

∴ Volume of canal = lxbxh

45000 = Area irrigatedx8 cm

45000 = Area irrigated x (8/100)m

Or, Area irrigated = 562500 m2 = 56.25 hectares.