Engineering :: Hydraulics Machines
|
|
|
|
|
|
| 61. |
A turbine develops 10000 kW under a head of 25 metres at 135 r.p.m. Its specific speed is |
| A. |
175.4 r.p.m. |
B. |
215.5 r.p.m. |
| C. |
241.5 r.p.m. |
D. |
275.4 r.p.m. |
Answer: Option C
Explanation:
|
| 62. |
Which of the following turbine is preferred for a specific speed of 60 to 300 r.p.m.? |
| A. |
Pelton wheel |
B. |
Francis turbine |
| C. |
Kaplan turbine |
D. |
none of these |
Answer: Option B
Explanation:
|
| 63. |
A Kaplan turbine is preferred for a specific speed of 300 to 1000 r.p.m. |
Answer: Option A
Explanation:
|
| 64. |
Which of the following trubine is preferred for 0 to 25 m head of water? |
| A. |
Pelton wheel |
B. |
Kaplan turbine |
| C. |
Francis turbine |
D. |
none of these |
Answer: Option B
Explanation:
|
| 65. |
A Francis turbine is used when the available head of water is |
| A. |
0 to 25 m |
B. |
25 m to 250 m |
| C. |
above 250 m |
D. |
none of these |
Answer: Option B
Explanation:
|
| 66. |
For 450 m head of water, |
| A. |
Pelton wheel |
B. |
Kaplan turbine |
| C. |
Francis turbine |
D. |
none of these |
Answer: Option A
Explanation:
|
| 67. |
A turbine is required to develop 1500 kW at 300 r.p.m. under a head of 150 m. Which of the following turbine should be used? |
| A. |
Pelton wheel with one nozzle |
B. |
Pelton wheel with two or more nozzles |
| C. |
Kaplan turbine |
D. |
Francis turbine |
Answer: Option A
Explanation:
|
| 68. |
A draft tube is used with impulse turbines. |
Answer: Option B
Explanation:
|
| 69. |
A Pelton wheel working under a constant head and discharge, has maximum efficiency when the speed ratio is |
Answer: Option C
Explanation:
|
| 70. |
The efficiency of a Pelton wheel working under constant head |
| A. |
remains same |
B. |
increases |
| C. |
decreases |
Answer: Option B
Explanation:
|
Read more:
|
|
