Engineering Questions with Answers - Multiple Choice Questions

# MCQs on Turbulent Boundary Layer on a Flat Plate

1 - Question

The main property that affects a boundary layer is__________
a) Temperature
b) Pressure
c) Viscosity
d) Surface tension

c
Explanation: A boundary layer is an important concept that refers to the layer of fluid. The fluid that is in the immediate vicinity of a bounding surface. The main property that affects a boundary layer is viscosity.

2 - Question

The layer that is influenced by a planetary boundary is called______
a) Atmospheric boundary layer
b) Lithosphere
c) Troposphere
d) Hydrosphere

a
Explanation: The planetary boundary layer is also called as atmospheric boundary layer(ABL). It is the lowest part of the atmosphere. The behaviour of ABL is directly influenced by its contact with the planetary surface.

3 - Question

What is the other name for Stoke’s boundary layer?
a) Momentum boundary layer
b) Atmospheric boundary layer
c) Oscillatory boundary layer
d) Thermal boundary layer

c
Explanation: Stoke’s boundary layer is also called as Oscillatory boundary layer. It is a boundary layer that is close to a solid wall. It moves in an oscillatory motion. It arrested by a viscous force acting in the opposite direction.

4 - Question

Eddy viscosity is a turbulent transfer of_________
a) Fluid
b) Heat
c) Momentum
d) Pressure

c
Explanation: Eddy viscosity is a turbulent transfer of momentum by eddies. It gives rise to an internal fluid friction. It is in analogous to the action of molecular viscosity in laminar fluid flow. Eddy viscosity takes place on a large scale.

5 - Question

The laminar boundary layer is a _________
a) Smooth flow
b) Rough flow
c) Uniform flow
d) Random flow

a
Explanation: For a laminar boundary layer the fluid moves in a very smooth flow. The laminar flow creates less skin friction drag. It is a less stable flow. The laminar boundary layer has got an increase in its thickness.

6 - Question

The turbulent boundary layer is a _________
a) Non-uniform with swirls
b) Uniform
c) Less stable
d) Smooth

a
Explanation: For a turbulent boundary layer the fluid moves in different direction producing swirls. It has more skin friction drag than that of laminar boundary layer. It is more stable when compared to laminar.

7 - Question

How do we measure the flow rate of liquid?
a) Coriolis method
b) Dead weight method
c) Conveyor method
d) Ionization method

a
Explanation: Coriolis concept of measurement of fluid takes place through the rotation with the reference frame. It is an application of the Newton’s Law. The device continuously records, regulates and feeds large volume of bulk materials.

8 - Question

How does a turbulent boundary layer produce swirls?
a) Due to random motion
b) Collision of molecules
c) Due to eddies
d) Due to non-uniform cross section

c
Explanation: For a turbulent boundary layer the fluid moves in different direction producing swirls. It produces swirls due to the presence of eddies. The smooth laminar boundary layer flow breaks down and transforms to a turbulent flow.

9 - Question

Define Viscosity.
a) Resistance to flow of object
b) Resistance to flow of air
c) Resistance to flow of fluid
d) Resistance to flow of heat

c
Explanation: Viscosity is developed due to the relative motion between two surfaces of fluids at different velocities. It happens due to the shear stress developed on the surface of the fluid.

10 - Question

The continuity equation of two- dimensional steady incompressible flow is_______