A. as an insulator
B. as a device for power factor improvement
C. for dielectric heating
D. for induction heating
Related Mcqs:
- In electric press, mica is used because it is _________ conductor of heat but/and __________ conductor of electricity?
A. bad, good
B. bad, bad
C. good, bad
D. good, good - In an electric room heat convector the method of heating used is______________?
A. arc heating
B. resistance heating
C. induction heating
D. dielectric heating - _________ has the highest value of thermal conductivity?
A. Copper
B. Aluminium
C. Brass
D. Steel - Heat is transferred simultaneously by condition, convection and radiation_____________?
A. inside boiler furnaces
B. during melting of ice
C. through the surface of the insulted pipe carrying steam
D. from refrigerator coils to freezer of a refrigerator - By which of the following methods the temperature inside arc nace can be varied ?
A. By disconnecting some of the heating elements
B. By varying the operating voltage
C. By varying the current through heating elements
D. By any of the above method - The process of heat transfer during the reentry of satellites and missiles, at very high speeds, into earth’s atmosphere is known as_______________?
A. ablation
B. radiation
C. viscous dissipation
D. irradiation - The temperature inside a furnace is usually measured by which of the following ?
A. Optical pyrometer
B. Mercury thermometer
C. Alcohol thermometer
D. Any of the above - Radiant heating is used for which of the following ?
A. Annealing of metals
B. Melting of ferrous metals
C. Heating of liquids in electric kettle
D. Drying of paints and varnishes - It is desirable to operate the arc furnaces at power factor of_____________?
A. zero
B. 0.707 lagging
C. unity
D. 0.707 leading - Properly of low temperature co-eflficient of heating element is desired due to which of the following reasons ?
A. To avoid initial rush of current
B. To avoid change in kW rating with temperature
C. Both (A) and (B)
D. Either (A) or (B)
