Answers

2015-10-26T16:04:13+05:30
Depth = 12dm = 1.2m
width = 30dm = 3m
flow velocity = 20km/h = 20,000 m/h
time = 30minute = 0.5 hour
standing water required = 9cm = 0.09m
Let the area = A m²

Volume of water will be same
1.2m × 3m × 20,000 m/h × 0.5 h = A × 0.09
⇒ A = 36000/0.09
⇒ A = 4,00,000 m² = 40 hectare

40 hectare plot can be irrigated
1 5 1