## Question

The fresh water behind a reservoir dam is 15 m deep. A horizontal pipe 4.0 cm in diameter passes through the dam 6.0 m below the water surface as shown in figure. A plug secures the pipe opening. The plug is removed. What volume of water flows out of the pipe in 3.0- hour?

### Solution

150 N

As the velocity of efflux,

.

so assuming the level of water in the tank to be constant [(i.e,, area = ∞) as it is not given] the volume coming out per second will be

So the volume of the water flowing through the pipe in 3 hour

.

#### SIMILAR QUESTIONS

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(Specific gravity of rod is 0.5).

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A wooden stick of length *L*, radius *R* and density has a small metal piece of mass *m* (of negligible volume) attached to its one end. Find the minimum value of the mass *m* (in terms of given parameters) that would make the stick float vertically in equilibrium in a liquid of density .

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A soap film is on a rectangular wire ring of size . If the size of the film is changed to , then calculate the work done in this process. The surface tension of soap film is .