Momentum and Mass Transfer

What is fluid mechanics?

• Study of fluid behaviour at rest

• Study of fluid behaviour in motion

• Study of fluid behaviour at rest and in motion

• Study of fluid behaviour at rest and in motion

What is fluid mechanics used for?

• Fluid mechanics enables to comprehend the behaviour of solid fluids under pressure

• Fluid mechanics enables to comprehend the behaviour of fluids under a variety of forces & atmospheric conditions

• Fluid mechanics enables to comprehend the behaviour of fluids under various temperatures only

• None of the mentioned

If a person studies about a fluid which is at rest, what will you call his domain of study?

• Fluid Dynamics

• Fluid Mechanics

• Fluid Statics

• Fluid Kinematics

What is the effect of increasing temperature on the density of a liquid?

• Decreases

• Increases

• Remains constant

• none of this

Which of the following best describes shear stress in a fluid?

• The force per unit area acting perpendicular to the fluid surface

• The force per unit area acting parallel to the fluid surface

• The pressure exerted by the fluid at rest

• The difference in pressure between two points in a fluid

_______ force per unit area acting perpendicular to the fluid surface.

• Normal stress

• Shear Stress

• Compressive stress

• tensile stress

In a Newtonian fluid, the shear stress is directly proportional to which of the following?

• Density of the fluid

• Velocity gradient (rate of change of velocity with respect to distance)

• Viscosity of the fluid

• Both B and C

What is the unit of shear stress in the SI system?

• Pascal (Pa)

• Newton (N)

• Joule (J)

• Meter per second (m/s)

For a fluid flowing in a pipe, where is the shear stress the highest?

• At the center of the pipe

• At the walls of the pipe

• Uniformly distributed throughout the pipe

• At a point midway between the center and the walls

Which of the following statements about shear stress in a fluid is correct?

• Shear stress is independent of the viscosity of the fluid.

• Shear stress is proportional to the square of the velocity gradient.

• Shear stress is zero in a fluid at rest.

• Shear stress is inversely proportional to the velocity gradient.