Shock Waves in Compressible Flows: Interactive Learning Quizzes

Question 1

Which of the following is NOT a requirement for shock wave formation in a compressible flow?

Accepted Answer

Viscosity

Answer

Supersonic flow

Answer

Irreversible entropy increase

Answer

Compression of the fluid

Question 2

Which type of flow is associated with the Prandtl-Meyer expansion fan?

Accepted Answer

Supersonic flow

Answer

Subsonic flow

Answer

Transonic flow

Answer

Hypersonic flow

Question 3

Which assumption is fundamental to the analysis of shock waves?

Accepted Answer

Inviscid flow

Answer

One-dimensional flow

Answer

Steady flow

Answer

Isothermal flow

Question 4

What is the nature of the entropy change across a shock wave?

Accepted Answer

Positive

Answer

Negative

Answer

Zero

Answer

Indeterminate

Question 5

Which quantities are related across a shock wave by the Rankine-Hugoniot equations?

Accepted Answer

Conservation of mass, momentum, and energy

Answer

Entropy and stagnation enthalpy

Answer

Density and temperature

Answer

Velocity and pressure

Question 6

The physical mechanism leading to the formation of detached shock waves is:

Accepted Answer

Supersonic flow over blunt bodies

Answer

Boundary layer separation

Answer

Sudden change in flow area

Answer

Interaction of multiple shock waves

Question 7

Which of the following is NOT a defining characteristic of shock waves?

Accepted Answer

Continuous pressure gradient

Answer

Abrupt change in flow properties

Answer

Irreversible process

Answer

Entropy increase

Question 8

For a normal shock wave, the Mach number upstream is:

Accepted Answer

Always greater than 1

Answer

Always less than 1

Answer

Either less than or greater than 1, depending on conditions

Answer

Always equal to 1

Question 9

Which of the following is the governing equation for one-dimensional, inviscid shock waves?

Accepted Answer

Rankine-Hugoniot equations

Answer

Euler equations

Answer

Navier-Stokes equations (incompressible)

Answer

Boundary layer equations

Question 10

What is the relationship between the upstream and downstream Mach numbers across a normal shock wave?

Accepted Answer

M1 > M2

Answer

M1 < M2

Answer

M1 = M2

Answer

M1 is undefined for normal shock waves

Question 11

In a converging-diverging nozzle, a shock wave can be generated when:

Accepted Answer

The flow is supersonic in the diverging section

Answer

The flow is subsonic in the diverging section

Answer

The flow is choked in the throat

Answer

The flow is laminar in the nozzle

Question 12

In a shock tube, the shock wave is typically generated by:

Accepted Answer

Bursting a diaphragm

Answer

Igniting a combustible mixture

Answer

Applying a pressure gradient

Answer

Using a piston

Question 13

What is the approximate Mach number of a shock wave in air at standard atmospheric conditions?

Accepted Answer

1.4

Answer

1.0

Answer

2.0

Answer

2.5

Question 14

Define the key characteristic of shock waves in compressible flows.

Accepted Answer

A sudden, discontinuous jump in flow properties

Answer

A gradual transition in flow properties

Answer

A wave that propagates at sonic speed

Answer

A wave that always induces a temperature increase

Question 15

Describe the primary distinction between a normal and an oblique shock wave.

Accepted Answer

The angle of the shock wave relative to the flow direction

Answer

The strength of the shock wave

Answer

The upstream Mach number

Question 16

Explain the practical significance of shock waves in supersonic aircraft design.

Accepted Answer

They can induce drag and reduce lift

Answer

They have no significant impact on aircraft performance

Answer

They enhance aircraft stability

Answer

They improve engine performance

Question 17

Explain the relationship between shock wave strength and its impact on downstream flow properties.

Accepted Answer

Stronger shock waves induce larger changes in flow properties

Answer

Stronger shock waves induce smaller changes in flow properties

Answer

Shock strength does not affect downstream flow properties

Question 18

In a shock wave, which of the following properties experience a discontinuous change?

Accepted Answer

Velocity, density, and pressure

Answer

Temperature and entropy

Answer

Enthalpy and specific heat

Answer

Mach number and Reynolds number

Question 19

The ratio of the static pressure downstream of a normal shock wave to the static pressure upstream is known as the:

Accepted Answer

Shock strength

Answer

Mach number

Answer

Stagnation pressure ratio

Answer

Density ratio

Question 20

Which of the following is a consequence of shock waves passing through a fluid?

Accepted Answer

Increase in entropy and loss of total pressure

Answer

No change in fluid properties

Answer

Conversion of kinetic energy into potential energy

Answer

Decrease in temperature and increase in velocity

Question 21

In a supersonic nozzle, a shock wave can form when:

Accepted Answer

The area of the nozzle decreases too rapidly

Answer

The fluid viscosity is too high

Answer

The area of the nozzle increases too rapidly

Answer

The flow rate is too low

Question 22

The major disadvantage of shock waves in fluid flows is their:

Accepted Answer

Loss of energy and increase in entropy

Answer

Instability and unpredictability

Answer

Potential for structural damage

Answer

Generation of high noise levels

Question 23

Which of the following assumptions is commonly made in the analysis of normal shock waves?

Accepted Answer

Flow is one-dimensional and steady

Answer

Fluid is incompressible and inviscid

Answer

Flow is compressible and viscous

Answer

Heat transfer and friction are significant