24 + Interview Questions in FLUIDS-IN-MOTION IN GENERAL AWARENESS Page 1 InterviewSolution

1.	A metal sphere of radius 1 mm falls vertically in glycerine Find the viscous force exerted by the glycerine on the sphere when the speed of the sphere is `1cm^(-1)` For glycerine . `eta=8.0 `poise .
Answer» Correct Answer - `1.5xx10^(-4)N`

Discussion

2.	A pitot tube dipped in a river and its gauge indicates 5cm of water column .What is the velocity of flow of water in the river?
Answer» Correct Answer - `0.99ms^(-1)`

Discussion

3.	An air bubble of diameter 2 cm is allowed to rise through a long cylindrical columu of viscous liquid and travels at the rate of 0.21 `cms^(-1)` If the density of the liquid is 1.47`g cm^(-3)` find the cofficient of vicosity .Given `g=9.8ms^(-2)` Density of air is to be neglecteed .
Answer» Correct Answer - `152.44Nsm^(-2)`

Discussion

4.	At what speed the velocity head of a stream of water be equal to 40 cm of Hg
Answer» Correct Answer - `10.362 ms^(-1)`

Discussion

5.	Alcohol flows through two capillary tubes under a constant pressure head the diameters of the two tubes are in the ratio of `4:1` and the lengths are in the ratio `4:1` Compare the rates of flow of alcohols through the two tubes .
Answer» Correct Answer - `64:1`

Discussion

6.	In normal adult the average speed of the though the aorta (which has a radius of 0.9 cm) is `0.33ms^(-1)` From the aorta ,the blood goes into major arteries which are 30 in number ,each of radius 0.5 Calculate the speed of blood through the arteries.
Answer» Correct Answer - `0.036ms^(-1)`

Discussion

7.	Velocity of flow of water in a horizontal pipe is `4.9 ms^(-1)` Find the velocity heat of water.
Answer» Correct Answer - 1.225 m

Discussion

8.	A pipe is running full of water. At a certain point `A` it tapers from `60 cm` diameter to `20 cm` diameter at `B`. The pressure difference between `A` and `B` is `100 cm` of water column. Find the rate of flow of water through the pipe.
Answer» Correct Answer - `1.4xx10^(5) cms^(-1)`

Discussion

9.	A garden hose having an internal diameter 2.0 cm is connected to a lawn sprinkle that consists of an enclosure with 24 holes , each 0.125 cm in diameter. If water in the hose has a speed of `90.0 cm s^(-1)` , find the speed of the water having the sprinkler hole.
Answer» Correct Answer - `9.6cms^(-1)`

Discussion

10.	The difference of height between the two limbs of a manometer connected at the ends of 20 cm long tube of 1 mm radius is 28 cm If 8 cm `8cm^(3)` of water is collected in 3 minutes ,calculate the coefficient of viscosity .
Answer» Correct Answer - 1.212 poise

Discussion

11.	Water is flowing though a cylindrical pipe of cross -sectional area 0.04 `pi m^(2)` at a speed of` 1.0 ms ^(-1)` If the diameter of the pipe is halved ,then find the speed of flow of water through it .
Answer» Correct Answer - `4.0ms^(-1)`

Discussion

12.	The diameter of the throat of a venturimeter is 6 cm .when it is inserted in a horizontal pipe line of diameter 10 cm the pressure difference between the pipe and the thraot equal 8 cm of water . Calulate the rate of flow.
Answer» Correct Answer - `3795 cm^(3) s^(-1)`

Discussion

13.	A spherical glass ball of mass `1.34xx10^(-4)` kg and diameter `4.4xx10^(-3)` m atakes 6.4 s to fall steadily thorugh a height of 0.381 m inside a large volume of oil of specitic gravity 0.943 Calcualte the visosity ifoil.
Answer» Correct Answer - 0.8025 `Nsm^(-2)`

Discussion

14.	The water entering a hauze flows with a speed of `0.1ms^(-1)` through a pipe of 21 mm inside diameter .What is the speed of water at a point ,where pipe tapers to a diameter of 7mm?
Answer» Correct Answer - `0.9ms^(-1)`

Discussion

15.	Calculate the mass of water flowing in 10 minutes throuth a tube 1 mm in diameter and 0.40 m long ,if there is a constant pressure heat of 20 cm of water . Coefficient of visosity of water is 0.00089 Pas.
Answer» Correct Answer - 0.08112 kg

Discussion

16.	One end of a horizontal pipe is closed with the help of a valve and the reading of a barometer attached in the pipe is `3xx10^(5)` pascal When the value in the pipe is opened then the reading of barometer falls to `10^(5)` pascal the velocity of water flowing through the pipe will be in m/s-
Answer» Correct Answer - `20ms^(-1)`

Discussion

17.	Water is flowing througth a horizontal tube of length 0.25 m and radius `4xx10^(-4)` m under a constant pressure head of 0.2 m of water , at the rate of `5xx10^(-6)` `m^(3)` per minture Calcutae the coefficient of viscosity of water .Density of water `=1000kgm^(-3)`
Answer» Correct Answer - `0.000945 decapoise`

Discussion

18.	It water flows horizontally through a pipe of varying cross section and the pressure of water equals `10 cm` of `Hg` at a point where the velocity of flow is `40 cm//s`, what is the pressure at another point where the velocity of flow is `50 cm//s`?
Answer» Correct Answer - 0.09966 m of Hg

Discussion

19.	Find the critical velocity for air flowing through a tube of 2cm diammeter .For air `rho=1.3xx10^(-3)gcm^(-3) and eta=181xx10^(-6)` poise
Answer» Correct Answer - `140cms^(-1)`

Discussion

20.	A metel plate 100 sq cm in area rests on a 2-mm layer of castor oil, whose coefficient of viscosity is `1.55` SI units. Calculate the horizontal force required to move the plate with a speed of 3 cm per second. [Hint: `F=-etaA(dv)/(dx)."Here"(dv)/(dx)=(3xx10^(-2)ms^(-1))/(2xx10^(-3))=15s^(-1)`.]
Answer» Correct Answer - 23250dyne

Discussion

21.	A tank cotaining water has an orifice 10 m below the surface of water in the tank . If there is no wastage of energy ,find the speed of discharge.
Answer» Correct Answer - `14ms^(-1)`

Discussion

22.	Water flows at the rate of 4 litres per second through an orifice at the bottom of tank which contains water 720 cm deep .Find the rate of escape of water if additionalpressure of 16 f/cm is applied at the surface of water.
Answer» Correct Answer - `19.28 litre s^(-1)`

Discussion

23.	A metal plate of area `0.02m^(2) ` is lying on a liquid layer of thickness `10^(-3)` m and coeffcient of viscosity 120 poise .Calcualate the horizontal force requirred to move the plate with a speed of `0.025ms^(-1)`
Answer» Correct Answer - 6 n

Discussion

24.	Calcualate speed of effux of kerosene from an orifice of a tank in which in the tank if therre contaning water has an orifice of an tank in which pressure is 4 atmosphere .Density of kerosene is 0.72 kg per litre .One atmosphere `=1 kg f cm^(-2)`.
Answer» Correct Answer - `33.5 ms^(-1)`

Discussion

Explore topic-wise InterviewSolutions in .

A metal sphere of radius 1 mm falls vertically in glycerine Find the viscous force exerted by the glycerine on the sphere when the speed of the sphere is `1cm^(-1)` For glycerine . `eta=8.0 `poise .

A pitot tube dipped in a river and its gauge indicates 5cm of water column .What is the velocity of flow of water in the river?

An air bubble of diameter 2 cm is allowed to rise through a long cylindrical columu of viscous liquid and travels at the rate of 0.21 `cms^(-1)` If the density of the liquid is 1.47`g cm^(-3)` find the cofficient of vicosity .Given `g=9.8ms^(-2)` Density of air is to be neglecteed .

At what speed the velocity head of a stream of water be equal to 40 cm of Hg

Alcohol flows through two capillary tubes under a constant pressure head the diameters of the two tubes are in the ratio of `4:1` and the lengths are in the ratio `4:1` Compare the rates of flow of alcohols through the two tubes .

In normal adult the average speed of the though the aorta (which has a radius of 0.9 cm) is `0.33ms^(-1)` From the aorta ,the blood goes into major arteries which are 30 in number ,each of radius 0.5 Calculate the speed of blood through the arteries.

Velocity of flow of water in a horizontal pipe is `4.9 ms^(-1)` Find the velocity heat of water.

A pipe is running full of water. At a certain point `A` it tapers from `60 cm` diameter to `20 cm` diameter at `B`. The pressure difference between `A` and `B` is `100 cm` of water column. Find the rate of flow of water through the pipe.

A garden hose having an internal diameter 2.0 cm is connected to a lawn sprinkle that consists of an enclosure with 24 holes , each 0.125 cm in diameter. If water in the hose has a speed of `90.0 cm s^(-1)` , find the speed of the water having the sprinkler hole.

The difference of height between the two limbs of a manometer connected at the ends of 20 cm long tube of 1 mm radius is 28 cm If 8 cm `8cm^(3)` of water is collected in 3 minutes ,calculate the coefficient of viscosity .

Water is flowing though a cylindrical pipe of cross -sectional area 0.04 `pi m^(2)` at a speed of` 1.0 ms ^(-1)` If the diameter of the pipe is halved ,then find the speed of flow of water through it .

The diameter of the throat of a venturimeter is 6 cm .when it is inserted in a horizontal pipe line of diameter 10 cm the pressure difference between the pipe and the thraot equal 8 cm of water . Calulate the rate of flow.

A spherical glass ball of mass `1.34xx10^(-4)` kg and diameter `4.4xx10^(-3)` m atakes 6.4 s to fall steadily thorugh a height of 0.381 m inside a large volume of oil of specitic gravity 0.943 Calcualte the visosity ifoil.

The water entering a hauze flows with a speed of `0.1ms^(-1)` through a pipe of 21 mm inside diameter .What is the speed of water at a point ,where pipe tapers to a diameter of 7mm?

Calculate the mass of water flowing in 10 minutes throuth a tube 1 mm in diameter and 0.40 m long ,if there is a constant pressure heat of 20 cm of water . Coefficient of visosity of water is 0.00089 Pas.

One end of a horizontal pipe is closed with the help of a valve and the reading of a barometer attached in the pipe is `3xx10^(5)` pascal When the value in the pipe is opened then the reading of barometer falls to `10^(5)` pascal the velocity of water flowing through the pipe will be in m/s-

Water is flowing througth a horizontal tube of length 0.25 m and radius `4xx10^(-4)` m under a constant pressure head of 0.2 m of water , at the rate of `5xx10^(-6)` `m^(3)` per minture Calcutae the coefficient of viscosity of water .Density of water `=1000kgm^(-3)`

It water flows horizontally through a pipe of varying cross section and the pressure of water equals `10 cm` of `Hg` at a point where the velocity of flow is `40 cm//s`, what is the pressure at another point where the velocity of flow is `50 cm//s`?

Find the critical velocity for air flowing through a tube of 2cm diammeter .For air `rho=1.3xx10^(-3)gcm^(-3) and eta=181xx10^(-6)` poise

A metel plate 100 sq cm in area rests on a 2-mm layer of castor oil, whose coefficient of viscosity is `1.55` SI units. Calculate the horizontal force required to move the plate with a speed of 3 cm per second. [Hint: `F=-etaA(dv)/(dx)."Here"(dv)/(dx)=(3xx10^(-2)ms^(-1))/(2xx10^(-3))=15s^(-1)`.]

A tank cotaining water has an orifice 10 m below the surface of water in the tank . If there is no wastage of energy ,find the speed of discharge.

Water flows at the rate of 4 litres per second through an orifice at the bottom of tank which contains water 720 cm deep .Find the rate of escape of water if additionalpressure of 16 f/cm is applied at the surface of water.

A metal plate of area `0.02m^(2) ` is lying on a liquid layer of thickness `10^(-3)` m and coeffcient of viscosity 120 poise .Calcualate the horizontal force requirred to move the plate with a speed of `0.025ms^(-1)`

Calcualate speed of effux of kerosene from an orifice of a tank in which in the tank if therre contaning water has an orifice of an tank in which pressure is 4 atmosphere .Density of kerosene is 0.72 kg per litre .One atmosphere `=1 kg f cm^(-2)`.