This set of Mechanical Operations Multiple Choice Questions & Answers (MCQs) focuses on “Leaf Filters”.
1. __________ is an exhaust gas driven compressor used to increase the power output.
b) Sonic boom
Explanation: A turbocharger is an exhaust gas driven compressor used to increase the power output of an internal combustion engine by compressing air that is entering the engine.
2. ________ consists of a row of rotor blades followed by a row of stator blades.
a) Centrifugal compressor
b) Axial compressor
c) Axial pump
d) Radial pump
Explanation: An axial compressor consists of a row of rotor blades followed by a row of stator blades and the working fluid traverses through these without significant change in radius.
3. The energy level of the fluid flowing through it is increased by the action of the __________
a) Rotor blades
b) Axial blades
c) Motor blades
d) Initial blades
Explanation: The energy level of the fluid flowing through it is increased by the action of the rotor blades, which exert a torque on the fluid supplied by an external source.
4. An axial compressor is a relatively _________ pressure ratio turbomachine.
Explanation: An axial compressor is a relatively low pressure ratio turbomachine with higher mass flow rate as compared to a centrifugal compressor.
5. Due to density variation from inlet to exit, the flow area _____________
c) Remains same
Explanation: Due to density variation from inlet to exit, the compressor end walls have flare with flow area reducing from inlet to exit.
6. In an axial turbine, the kinetic energy of combustion gas is converted to mechanical power by _________
a) Shear action
b) Axial action
c) Impulse action
d) Tear action
Explanation: The kinetic energy of combustion gas is converted to mechanical power by the its impulse or reaction with a series of blades arranged around the circumference of a wheel or cylinder.
7. ________ is one where the change in head is brought about primarily by a change in velocity.
a) Impulse turbine
b) Reaction turbine
c) Axial turbine
d) Radial Turbine
Explanation: An impulse turbine i.e. Pelton wheel or water wheel is one where the change in head is brought about primarily by a change in velocity.
8. Calculate NRe , if diameter is 12 m and impellor takes 20 rotations and density and viscosity are 1.20 and 200?
Explanation: As NRe is given as (122*20*1.20/200) = 17.28.
9. Calculate NFr, if impellor takes 15 rotations and 1.2 m in diameter?
Explanation: As NFr = (225*1.2/g) = 225*1.2/32.2 = 8.38.
10. Calculate power, if Q is 4.50 m3/s and at a height of 2 m and consider water as fluid?
Explanation: As P = Qph = 4.50*2*1000 = 900 lb/s.
Sanfoundry Global Education & Learning Series – Mechanical Operations.
To practice all areas of Mechanical Operations, here is complete set of 1000+ Multiple Choice Questions and Answers.