A. conduction
B. convection
C. radiation
D. any of the above
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Related Mcqs:
- The value of exciting or magnetizing current depends upon which of the following factors ?
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- A. Power density B. Temperature difference between heated surface and coolant C. Thermal resistivity, density, specific heat D. Gravitational constant E. All of the above...
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- A. Conduction B. Convection C. Radiation D. All of the above...
- If an insulating material is operated beyond the maximum allowable temperature, its life is_____________?
- A. drastically increased B. drastically reduced C. unaffected D. none of the above...
- The time taken by the machine to attain 0.632 of its final steady temperature rise is called_____________?
- A. heating time constant B. cooling time constant C. either A. or B. D. none of the above...
- In _________ machines, the size of the shaft is decided by the critical speed which depends on the deflection of the shaft?
- A. small B. medium C. large D. any of the above....
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- A. conduction B. convection E. radiation D. any ofthe above...
- Hydrogen has a heat transfer co-efficient __________ times that of air?
- A. 1.5 B. 2.5 C. 3.5 D. 4.5...
- The heat dissipating capability of transformers of ratings higher than 30 kVA in increased by providing which of the following ?
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