﻿ Water flows into a horizontal pipe whose one end is closed with a valve and the reading of a pressure gauge attached to the pipe is . This reading of the pressure gauge falls to  when the valve is opened. Calculate the speed of water flowing into the pipe. : Kaysons Education

# Water Flows Into A Horizontal Pipe Whose One End Is Closed With A Valve And The Reading Of A Pressure Gauge Attached To The Pipe Is . This Reading Of The Pressure Gauge Falls To  when The Valve Is Opened. Calculate The Speed Of Water Flowing Into The Pipe.

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## Question

### Solution

Correct option is

20 m/s

According to Bernoulli’s theorem, we have

Here v1 = 0 (the valve is initially closed, and so the velocity of water is zero).

.

Here  (for water)

= 400 m2/s2

or       v2 = 20 m/s.

#### SIMILAR QUESTIONS

Q1

The critical velocity of an oil drop in air is . What is the radius of the drop? If two such drops coalesce than what will be the terminal velocity of the resultant drop. Coefficient of viscosity of oil is  and density is . The density of air in comparison to oil is negligible and .

Q2

A metal sphere of diameter  enters water after falling a distance h freely in the gravitational field of the earth. After entrance in water, its velocity remains unchanged. Calculate the value of h. The coefficient of viscosity of water , density of water  and acceleration due to gravity = 10 N/kg.

Q3

An air bubble of radius 1.0 mm rises with uniform velocity through a viscous liquid of density 1625 kg/m3. Calculate the velocity of the bubble if the coefficient of viscosity of the liquid is 10 poise and the density of air is negligible. (g = 10 m/s2).

Q4

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Q5

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Q6

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Q7

Water is flowing through two horizontal pipes of different diameters which are connected together. In the first pipe the speed of water is 4.0 m/s and the pressure is . Calculate the speed and pressure of water in the second pipe. The diameters of the pipes are 3.0 cm and 6.0 cm respectively.

Q8

A liquid is kept in a cylindrical vessel which is being rotated about its axis. The liquid rises at the sides. If the radius of the vessel is 0.05 m and the speed of rotation is 2 rev/s, find the difference in the heights of liquid at the centre of the vessel and at its sides.

Q9

The pressure difference between two points along a horizontal pipe, through which water is flowing, is 1.4 cm of mercury. If, due to non-uniform cross-section, the speed of flow of water at the point of greater cross-section is 60 cm/s, calculate the speed at the other point. Density of mercury .

Q10

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