| 1. | In reaction turbines, the axial thrust is due to ? | |
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pressure drop across the rotor
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change in axial velocity
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both (a) and (b)
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none of these
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Report Question| 2. | The density of supersaturated steam is about.............. that of the ordinary saturated vapour at the corresponding pressure ? | |
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same as
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2 times
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4 times
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8 times
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| 3. | In a nozzle, whole frictional loss is assumed to occur between ? | |
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inlet and thoroat
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inlet and outlet
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throat and exit
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all of these
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| 4. | The value of the reheat factor varies from ? | |
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1.02 to 1.06
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1.08 to 1.10
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1.2 to 1.6
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1.6 to 2
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| 5. | The isentropic enthalpy drop in moving blade is two-third of the isentropic enthalpy drop in fixed blades of a turbine. The degree of reaction will be ? | |
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0.4
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0.56
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0.67
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1.67
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| 6. | The ratio of total useful heat drop to the total isentropic heat drop, is called ? | |
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stage efficiency
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internal efficiency
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Rankine efficiency
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none of these
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| 7. | The effect of bleeding is that ? | |
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it increases the thermodynamic efficiency of the turbine
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boiler is supplied with hot water
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it decreases the power developed by the turbine
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all of the above
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| 8. | In an impulse reaction turbine, the pressure drops gradually and continuously over ? | |
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fixed blades
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moving blades
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both fixed and moving blades
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none of these
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| 9. | Thermal equilibrium means that the flow of steam is ? | |
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isothermal
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isentropic
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hyperbolic
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polytropic
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| 10. | The effect of friction on the flow of steam through a nozzle is to ? | |
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decrease the mass flow rate and to increase the wetness of steam
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increase the mass flow rate and to increase the exit temperature
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decrease the mass flow rate and to decrease the wetness of steam
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increase the exit temperature without any effect on mass flow rate
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