Water flows into a tank 180 m × 140 m through a rectangular pipe of 1.2m × 0.75 m at a rate of 15 km/h. In what time will the water rise by 4 m?
Answer & explanation
Correct answer: option 2
Let 'x' hours the water level in the tank rise by 4 m.
Discharge of water = Volume of tank upto water level in the tank.
Discharge of water = Area of cross-section of pipe × velocity of flow,
From above formulae,
⇒ Area of cross-section of pipe × Velocity of flow = Volume of a tank upto water level in the tank
⇒ 1.2 × 0.75 × 15000 × x = 180 × 140 × 4
⇒ x = \(\frac{1121}{5}\)
⇒ x = 7 hours 28 minutes.
Therefore, the water level will rise by 4 m in 7 hours 28 minutes.