15. Water in a canal, 5.4 m wide and 1.8 m deep, is flowing with a speed of 25 km/hour.
How much area can it irrigate in 40 minutes, if 10 cm of standing water is required
for irrigation ?
Answers
Answer:
Step-by-step explanation:
Breadth , b = 5.4 m
Height[depth] , h = 1.8 m
Speed of canal = 25 km/hr
Length of canal in 1 hour = 25 km
Length of canal in 60 minutes = 25 km [ 1 hr = 60 min ]
Length of canal in 1 min = \frac{25}{60}
Length of canal in 40 min = \frac{25}{60} × 40
= 16.67 km [ approx . ]
= 16670 m
Volume of canal = l b h
= 16670 × 5.4 × 1.8 m
= 162032.4 metres
Height of standing water = 10 cm = 0.1 metres
Volume of water in canal = Volume of area irrigated
Volume of area irrigated = Area irrigated × height
162032.4 metres = Area irrigated × 0.1
Area irrigated = 162032.4 ÷ 0.1
= 1620324 m²
1m² = 0.0001 hectares
Area irrigated = 162.0324 hectares
hope it's helpful