Question

Ex 13.3, 8
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

Answer:

56.25 hectares

Step-by-step explanation:

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

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

= 5000m × 6m × 1.5m = 45000 m³

Let area of field = x m²

Then, volume of water irrigates into the field = area of field × height of water during irrigation

= x m² × 8× 10⁻² m = 0.08x m³

Now, volume of water flowing from canal = volume of water in field

45000 m³ = 0.08x m³

x = 562500 m²

We know, 1 hectare = 10000 m²

So, area of field in hectare = 562500/10000 = 56.25 hectares