Question

Water in a canal 5m wide and 6m deep is with a speed of 10km/hr. How much area will it irrigate in 30 minute if 8 cm of standing water is desired?

Answer 1

Speed of flowing of water from canal is $10km/h$ , means length of water flows in $1hour=10km$ , so length of water flows in $30minutes=5km$.

Now, volume of water flowing from canal $=$ length of water flows in $30minutes\times$ breadth of canal $\times$ deep of canal

$=5000\times 5\times 6$

$=150000m^3$

Let the area irrigated $=x{m}^2$

Standing water height be $h=8cm=\frac{8}{100}=0.08m$

$\therefore$ $x\times 0.08=150000$

$\therefore$ $x=\frac{150000}{0.08}=2343750m^2$

Since $1$ hectare $=10000m^2$

$\therefore$ The area irrigated $=234.375hectare$