Speed of flowing water = 10 km/hr
In 30 minutes length of flowing water =10 × \(\frac{30}{60}\) km
= 5 km = 5000 m
Volume of flowing water in 30 minutes = 5000 × width × depth
Width of canal = 1.5 m
Depth of canal = 6 m
Volume of canal = 5000 × 1.5 × 6 m3
= 45000 m3
Irrigated area in 30 minutes if 8 cm of flowing water is required
= \(\frac{45000}{0.08}\)
= 562500 m2
