Question

Question no.8 please do it

Answer 1

Width of canal = 6 m

Depth of canal = 1.5 m

Flow rate of water = 10 km/h

Distance= speed × time

Distance travelled by the water in 30 minutes = 1000×1/2 = 500m

Amount of water irrigated in 20 minutes

= 6 x 1.5 x 500 m3

= 4500 m3

Area irrigated by this water if 8 cm standing water is desired i.e 8cm = 0.08 m

= 4500 / 0. 08 m2

= 56250 m2

= 0.05625 km2. 2)

Given that diameter of the cylindrical tank = 10 m Radius of the cylindrical tank (r) = 5 m Height of the cylindrical tank (H) = 2 m

Volume of cylindrical tank = πr2H = π × 52× 2 = 50 π m3 Internal Diameter of the pipe (d) = 20 cm Internal Radius of the pipe (r) = 10 cm = (1/10) = 0.1 m Rate of flow of water = 3 km /hr = 3000 m/ hr. So that volume of water that flows in t hours from the pipe = Area of cross section of pipe × speed × time = π(1/10)2 x 3000 x t = 30πt m3 ∴ Volume of water that flows from the pipe into the tank in "t" hours = volume of the tank

⇒ 30 π t = 50 π

⇒ 30 t = 50 ⇒ t = 50 / 30 hrs ⇒ t = 5 / 3 hrs = 1 hr 40 min = 100 minutes.

Answer 2

Answer:

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