Question

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

Breadth of a canal, b = 6 m. 

Height, h = 1.5 m 

Speed of water =10 km/hr. 

Quantity of water = 8 cm. 

Quantity of water flowing in 30 minutes? 

Volume of water flowing in 60 minutes, 

= (10 × 1000) × 6 × 1.5 cm³ . 

( ∵ Speed = 10 km/hr.; 10 × 1000 m/hr.) 

Volume of water flowing in 30 minutes,

= 10000 x 9 x \(\frac{30}{60}\)m³

∴ Let the area of land be ‘x’ sq.m.

x= 562500 sq.m.