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# Viscosity MCQ Questions - Fluid Mechanics

Viscosity MCQs : Here you will find MCQ Questions related to "Viscosity" in Fluid Mechanics. These Viscosity MCQ Questions Will help you to improve your Fluid Mechanics knowledge and will prepare you for various Examinations like Competitive Exams, Placements, Interviews and other Entrance Exmaniations

Question 1

Water flows between two plates of which the upper one is stationary and the lower one is moving with a velocity V. What will be the velocity of the fluid in contact with the upper plate?

A. V
B. 2V
C. N ⁄ 2
D. 0

Question 2

The viscous force the relative motion between the adjacent layers of a fluid in motion.Which one of the flowing fits best in the sentence?

A. opposes
B. never affects
C. facilitates
D. may effect under certain conditions

Question 3

The viscosity of a fluid in motion is 1 Poise. What will be it’s viscosity (in Poise) when the fluid is at rest?

A. 0
B. 0.5
C. 1
D. 1.5

Question 4

Which of the following correctly states how the viscosities of a liquid and a gas will change with temperature?

A. Viscosity increases with the increase in temperature of a liquid and decreases with the increase in temperature of a gas
B. Viscosity increases with the increase in temperature of a liquid and increases with the increase in temperature of a gas
C. Viscosity decreases with the increase in temperature of a liquid and decreases with the increase in temperature of a gas
D. Viscosity decreases with the increase in temperature of a liquid and increases with the increase in temperature of a gas

Question 5

The kinematic viscosity of a fluid is 0.1 Stokes. What will be the value is (m^2)/s?

A. 10^-2
B. 10^-3
C. 10^-4
D. 10^-5

Question 6

Two horizontal plates placed 250mm have an oil of viscosity 20 poises. Calculate the shear stress in oil if upper plate is moved with velocity of 1250mm/s.

A. 20 N/m^2
B. 2 N/m^2
C. 10 N/m^2
D. 1 N/m^2

Question 7

In which types of fluids it is observed that momentum transfer dominates cohesive forces with increase in temperature and hence viscosity increases

A. Liquids
B. Gases
C. Solids
D. All of the above

Question 8

What is the characteristic variation shown by the thixotropic fluids in their shear stress vs. rate of shear strain graph?

A. shear stress increases with increase in rate of shear strain
B. shear stress decreases with increase in rate of shear strain
C. shear stress shows variation only after a definite shear stress is reached
D. shear stress has decreasing constant and then variation relationship with rate of shear strain

Question 9

Kinematic viscosity depends on density and dynamic viscosity

A. TRUE
B. FALSE
C. Can be true or false
D. Can not say

Question 10

What happens to viscosity in the case of incompressible fluids as temperature is increased

A. It remains constant
B. It increases
C. It decreases
D. None of the above