MCQOPTIONS
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MCQOPTIONS
This section includes 40 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Discharge of a centrifugal pump is (where = Speed of the pump impeller) |
| A. | directly proportional to |
| B. | inversely proportional to |
| C. | directly proportional to |
| D. | inversely proportional to |
| Answer» B. inversely proportional to | |
| 2. |
The discharge of a double acting reciprocating pump is (where = Length of stroke, = Cross-sectional area of piston, and = Speed of crank in r.p.m.) |
| A. | . |
| B. | . |
| C. | 2 |
| D. | . |
| E. | . |
| Answer» E. . | |
| 3. |
When the speed of the pump increases, its net positive suction head () requirement decreases. |
| A. | Agree |
| B. | Disagree |
| Answer» C. | |
| 4. |
Manometric head is the actual head of water against which a centrifugal pump has to work. |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 5. |
A Francis turbine is an outward flow reaction turbine. |
| A. | True |
| B. | False |
| Answer» C. | |
| 6. |
The efficiency of a reaction turbine for a given head __________ with the increase in speed. |
| A. | decreases |
| B. | increases |
| Answer» B. increases | |
| 7. |
In an impulse turbine, the pressure of water both at entering and leaving the vanes, is atmospheric. |
| A. | Agree |
| B. | Disagree |
| Answer» B. Disagree | |
| 8. |
If the net positive suction head () requirement for the pump is not satisfied, then |
| A. | no flow will take place |
| B. | cavitation will be formed |
| C. | efficiency will be low |
| D. | excessive power will be consumed |
| Answer» C. efficiency will be low | |
| 9. |
The width of the bucket for a Pelton wheel is generally __________ the diameter of jet. |
| A. | double |
| B. | three times |
| C. | four times |
| D. | five times |
| Answer» E. | |
| 10. |
For 450 m head of water, __________ shallbeused. |
| A. | Pelton wheel |
| B. | Kaplan turbine |
| C. | Francis turbine |
| D. | none of these |
| Answer» B. Kaplan turbine | |
| 11. |
In a Francis turbine, the pressure at inlet is __________ that at outlet. |
| A. | less than |
| B. | more than |
| Answer» C. | |
| 12. |
If the Francis turbine is run below 50 percent head for a long period, it will not only lose its efficiency but also the cavitation danger will become more serious. |
| A. | Agree |
| B. | Disagree |
| Answer» B. Disagree | |
| 13. |
In a mixed flow reaction turbine, the flow of water is partly radial and partly axial. |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 14. |
A Pelton wheel with one nozzle is preferred for a specific speed between 35 to 60 r.p.m. |
| A. | True |
| B. | False |
| Answer» C. | |
| 15. |
In a centrifugal pump, the water enters the impeller __________ and leaves the vanes axially. |
| A. | axially |
| B. | radially |
| Answer» C. | |
| 16. |
A Kaplan turbine is an axial flow reaction turbine. |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 17. |
The hydraulic efficiency of an impulse turbine is maximum when velocity of wheel is __________ of the jet velocity, |
| A. | one-fourth |
| B. | one-half |
| C. | three-fourth |
| D. | double |
| Answer» C. three-fourth | |
| 18. |
The overall efficiency of an impulse turbine is the ratio of the actual power produced by the turbine to the energy actually supplied by the turbine. |
| A. | Yes |
| B. | No |
| Answer» B. No | |
| 19. |
The efficiency of jet propulsion for a ship with inlet orifices at right angles to the direction of motion of ship, will be maximum when the relative velocity of the jet and ship is equal to twice the velocity of the ship. |
| A. | Yes |
| B. | No |
| Answer» B. No | |
| 20. |
The action of a centrifugal pump is that of a reversed reaction turbine. |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 21. |
A hydraulic intensifier is a device used to increase the intensity of pressure of water by means of energy available from a large quantity of water at a low pressure. |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 22. |
The power developed by a turbine is (where = Head of water under which the turbine is working) |
| A. | directly proportional to |
| B. | inversely proportional to |
| C. | directly proportional to |
| D. | inversely proportional to |
| Answer» D. inversely proportional to | |
| 23. |
A jet of water enters and leaves a fixed curved vane tangentially. The force of jet along perpendicular to the vane is zero. |
| A. | True |
| B. | False |
| Answer» C. | |
| 24. |
In a mixed flow centrifugal pump, the flow through the impeller is a combination of radial and axial flows. |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 25. |
Power required to drive a centrifugal pump is __________ proportional to N. |
| A. | directly |
| B. | inversely |
| Answer» B. inversely | |
| 26. |
A reciprocating pump is also called a __________ displacement pump. |
| A. | positive |
| B. | negative |
| Answer» B. negative | |
| 27. |
The head available at the inlet of the turbine is known as net or effective head. |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 28. |
In an axial flow reaction turbine, the water flows __________ to the axis of the wheel. |
| A. | parallel |
| B. | perpendicular |
| Answer» B. perpendicular | |
| 29. |
The air vessel, in a reciprocating pump, is a cast iron closed chamber having an opening at its base. |
| A. | Agree |
| B. | Disagree |
| Answer» B. Disagree | |
| 30. |
A Kaplan turbine is preferred for a specific speed of 300 to 1000 r.p.m. |
| A. | Yes |
| B. | No |
| Answer» B. No | |
| 31. |
In a reaction turbine, the water enters the wheel under pressure and flows over the vanes. |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 32. |
The gross or total head of the turbine is the __________ of the water levels at the head race and tail race. |
| A. | sum |
| B. | difference |
| C. | product |
| Answer» C. product | |
| 33. |
The specific speed of a centrifugal pump may be defined as the speed of an imaginary pump, identical with the given pump, which will discharge one litre of water, while it is being raised through a head of one metre. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 34. |
The power of a centrifugal pump working under constant head and discharge increases with the speed. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 35. |
A jet of water is striking at the centre of a curved vane moving with a uniform velocity in the direction of jet. For the maximum efficiency, the vane velocity is __________ of the jet velocity |
| A. | one-half |
| B. | one-third |
| C. | two-third |
| D. | three-fourth |
| Answer» C. two-third | |
| 36. |
A draft tube is used with impulse turbines. |
| A. | Yes |
| B. | No |
| Answer» C. | |
| 37. |
If the ratio of corresponding velocities at corresponding points are equal, then the model and the prototype are said to have dynamic similarity. |
| A. | Correct |
| B. | Incorrect |
| Answer» C. | |
| 38. |
A reciprocating pump is suitable for less discharge and higher heads. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 39. |
A hydraulic accumulator is a device used to store __________ energy which may be supplied to a machine later on. |
| A. | strain |
| B. | pressure |
| C. | kinetic |
| Answer» C. kinetic | |
| 40. |
The discharge through a turbine is |
| A. | directly proportional to |
| B. | inversely proportional to |
| C. | directly proportional to |
| D. | inversely proportional to |
| Answer» B. inversely proportional to | |