| 1. | When the back pressure of a nozzle is below the designed value of pressure at exit of nozzle, the nozzle is said to be ? | |
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choked
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underdamping
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overdamping
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none of these
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Report Question| 2. | The ratio of the work done on the blades per kg of steam to the total energy supplied per stage per kg of steam is called ? | |
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blading efficiency
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nozzle efficiency
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stage efficiency
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mechanical efficiency
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| 3. | In turbines, the fluid undergoes a continuous steady flow process and the speed of flow is ? | |
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low
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very low
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high
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very high
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| 4. | In a reaction turbine ? | |
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the steam is allowed to expand in the nozzle, where it gives a high velocity before it enters the moving blades
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the expansion of steam takes place partly in the fixed blades and partly in the moving blades
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the steam is expanded from a high pressure to a condenser pressure in one or more nozzles
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the pressure and temperature of steam remains constant
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| 5. | The compounding of turbines is done in order to ? | |
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reduce speed of rotor
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improve efficiency
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reduce exit losses
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all of these
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| 6. | Which of the following statement is correct ? | |
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The efficiency of steam turbines is greater than steam engines
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A flywheel is a must for steam turbine
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The turbine blades do not change the direction of steam issuing from the nozzle
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The pressure of steam, in reaction turbines, is increased in fixed blades as well as in moving blades
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| 7. | In an impulse turbine, steam expands ? | |
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wholly in blades
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wholly in nozzle
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partly in the nozzle and partly in blades
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none of these
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| 8. | De-Laval turbines are mostly used ? | |
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where low speeds are required
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for small power purposes and low speeds
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for large power purposes
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for small power purposes and high speeds
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| 9. | The flow of steam is super-sonic ? | |
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at the entrance to the nozzle
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at the throat of the nozzle
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in the convergent portion of the nozzle
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in the divergent portion of the nozzle
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| 10. | A stag in reaction turbine, is represented by ? | |
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number of casing
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number of entries of steam
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number of exits of steam
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each row of blades
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