# 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
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.

b. tangential and axial
d. unpredictable

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

b. Tangential and axial
d. None of the existing

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

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!