Introduction to Turbo Machines - Mechanical Engineering (MCQ) questions and answers

1)   Consider the below diagram of jet of water striking flat stationary plate normal to jet. What will be the phase of workdone on the plate?

a. negative
b. positive
c. zero
d. unpredictable
Answer  Explanation 

ANSWER: zero

Explanation:
No explanation is available for this question!


2)   The radial force in rotodynamic machine, which is developed by rate of change of momentum in radial velocity, is taken care by__________.

a. journal bearing
b. radial thrust bearing
c. both a. and b.
d. none of the above
Answer  Explanation 

ANSWER: journal bearing

Explanation:
No explanation is available for this question!


3)   The product of force (F) and time (t) is called as________.

a. momentum
b. work done
c. impulse
d. pressure
Answer  Explanation 

ANSWER: impulse

Explanation:
No explanation is available for this question!


4)   What is the formula for forces exerted by fluid on a body?

a. (Rate of momentum in) x (Rate of momentum out)
b. (Rate of momentum in) – (Rate of momentum out)
c. (Rate of momentum in) + (Rate of momentum out)
d. None of the above
Answer  Explanation 

ANSWER: (Rate of momentum in) – (Rate of momentum out)

Explanation:
No explanation is available for this question!


5)   Meridonial velocity is the resultant of _____________ components of fluid velocity.

a. radial and tangential
b. tangential and axial
c. radial and axial
d. unpredictable
Answer  Explanation 

ANSWER: radial and axial

Explanation:
No explanation is available for this question!


6)   _______________ components of fluid velocity have the responsibility of the transportation of fluid through the machine.

a. Radial and tangential
b. Tangential and axial
c. Radial and axial
d. None of the existing
Answer  Explanation 

ANSWER: Radial and axial

Explanation:
No explanation is available for this question!


7)   Which component of fluid velocity is responsible for transmission of power through rotodynamic machine?

a. Radial
b. Axial
c. Tangential
d. None of the above
Answer  Explanation 

ANSWER: Tangential

Explanation:
No explanation is available for this question!


8)   What is the general energy equation for transfer of energy between the fluid and machine?

Where,
Vw1 = Tangential component of the velocity of fluid at the entry of the rotor
Vw2 = Tangential component of the velocity of fluid at the exit of the rotor
u1 = Peripheral velocity of fluid at the entry of the rotor
u2 = Peripheral velocity of fluid at the exit of the rotor
ṁ = Flow rate of fluid


a. E = ṁ (Vw1 – Vw2) x (u1 – u2)
b. E = ṁ (Vw1 – Vw2) / (u1 – u2)
c. E = ṁ (Vw1 u1 – Vw2 u2)
d. E = ṁ (Vw1 u1 – Vw2 u2)2
Answer  Explanation 

ANSWER: E = ṁ (Vw1 u1 – Vw2 u2)

Explanation:
No explanation is available for this question!


9)   If (Vw1 u1 – Vw2 u2), then machine is called as________.

a. compressor
b. turbine
c. pump
d. all of the above
Answer  Explanation 

ANSWER: turbine

Explanation:
No explanation is available for this question!


10)   Consider the following diagram of jet of water striking flat stationary plate inclined at an angle θ. What will be the phase of workdone on the plate?

a. negative
b. positive
c. zero
d. unpredictable
Answer  Explanation 

ANSWER: zero

Explanation:
No explanation is available for this question!