Test: Compressible Flow & Flow Through Open Channel - 1 - Mechanical Engineering MCQ

Assertion (A): In a supersonic nozzle, with sonic condition at the throat, any reduction of down stream pressure will not be felt at the inlet of the nozzle. 
Reason (R): The disturbance caused downstream of supersonic flowstravels at sonic velocity which cannot propagate upstream by Machcone.

Consider the following statements pertaining to isentropic flow:
1. To obtain stagnation enthalpy, the flow need not be decelerate disentropically but should be decelerated adiabatically.
2. The effect of friction in an adiabatic flow is to reduce the stagnation pressure and increase entropy.
3. A constant area tube with rough surfaces can be used as a subsonicnozzle.
Of these correct statements are:  

The Mach number at inlet of gas turbine diffuser is 0.3. The shape of the diffuser would be:  

Consider the following statements: 
1. De Laval nozzle is a subsonic nozzle.
2. Supersonic nozzle is a converging passage.
3. Subsonic diffuser is a diverging passage.
Which of these statements is/are correct?

Consider the following statements: 
A convergent-divergent nozzle is said to be choked when
1. Critical pressure is attained at the throat.
2. Velocity at the throat becomes sonic.
3. Exit velocity becomes supersonic.
Of these correct statements are

Consider the following statements :
Choked flow through a nozzle means:
1. Discharge is maximum
2. Discharge is zero
3. Velocity at throat is supersonic
4. Nozzle exit pressure is less than or equal to critical pressure.
Which of the above statements is/are correct?

Consider the following statements in relation to a convergent divergent steam nozzle operating under choked conditions:  
1. In the convergent portion steam velocity is less than sonic velocity
2. In the convergent portion steam velocity is greater than sonicvelocity
3. In the divergent portion the steam velocity is less them sonicvelocity
4. In the divergent portion the steam velocity is greater than sonicvelocity
Which of the above statements are correct?

Which one of the following is correct?  
For incompressible flow a diverging section acts as a diffuser for upstream flow which is:

In turbulent flow over an impervious solid wall  

Match List-I (Flow depth) with List-II (Basic hydraulic condition associated there with) and select the correct answer:  

How is the best hydraulic channel cross-section defined? 

Assertion (A): To have maximum hydraulic efficiency, the trapezoidal section of an open channel should be a half-hexagon 
Reason (R): For any cross-section, a hexagon has the lest-perimeter.

A hydraulic jump occurs in a channel 

Consider the following statements: 
A hydraulic jump occurs in an open channel
1. When the Froude number is equal to or less than one.
2. At the toe of a spillway.
3. Downstream of a sluice gate in a canal.
4. When the bed slope suddenly changes.
Which of these are correct?

A sluice gate discharges water into a horizontal rectangular channel with a velocity of 12 m/s and depth of flow of 1 m. What is the depth offlow after the hydraulic jump?  

An open channel flow encounters a hydraulic jump as shown in the figure. The following fluid flow conditions are observed between A andB: 
1. Critical depth
2. Steady non-uniform flow
3. Unsteady non-uniform flow
4. Steady uniform flow.
The correct sequence of the flow conditions in the direction of flow is:

A hydraulic jump is formed in a 5.0 m wide rectangular channel with sequent depths of 0.2 m and 0.8 m. The discharge in the channel, inm³/s, is: