Electric Heating MCQs

1. The best suitable material for the heating element is

  1. Tungsten
  2. Nichrome
  3. Manganin
  4. Carbon

Answer
Answer. b

2. Which electrodes used in arc furnaces are obtained by heating at very high temperature?

  1. Carbon electrodes
  2. Self baking electrodes
  3. Graphite electrodes
  4. Electrochemical electrodes

Answer
Answer. c

3. For arc heating, the electrodes used are made of

  1. Aluminium
  2. Tungsten
  3. Copper
  4. Graphite

Answer
Answer. d

4. Inductance furnaces are used for

  1. Melting of aluminium
  2. Heating of insulator
  3. Heat treatment of casting
  4. All of the above

Answer
Answer. c

5. Which of the following devices is necessarily required for automatic temperature control in a furnace?

  1. Thermocouple
  2. Thermostat
  3. Auto-transformer
  4. Heating elements of variable resistance

Answer
Answer. b

6. The method suitable for heating of a conducting medium is

  1. Induction heating
  2. Indirect arc heating
  3. Eddy current heating
  4. Resistance heating

Answer
Answer. a

7. Which of the following methods of heating is not dependent on the frequency of supply?

  1. Induction heating
  2. Dielectric heating
  3. Electric resistance heating
  4. All of the above

Answer
Answer. c

8. If a 220V heater is used on 110V supply, the heat produced by it will be nearly

  1. One half 
  2. Twice
  3. One-fourth
  4. Four times

Answer
Answer. c

9. An electric heater draws 3.5A from a 110V source. The resistance of the heating element is approximately?

  1. 38.5 Ω
  2. 31 Ω
  3. 385 Ω
  4.  3.1 Ω

Answer
Answer. b

10. Dielectric heating is also called

  1. Volume heating
  2. Infrared heating
  3. Surface heating
  4. Eddy current heating

Answer
Answer. a

11. Which of the following is of high importance in case of induction heating?

  1. Voltage
  2. Frequency
  3. Current
  4. All the above

Answer
Answer. b

12. For arc heating, the electrodes are made of

  1. Copper
  2. Aluminium
  3. Graphite
  4. ACSR conductor

Answer
Answer. c

13. Furnaces used for cremation use

  1. Dielectric heating
  2. Arc heating
  3. Resistance heating
  4. Induction heating

Answer
Answer. c

14. A geyser is operated from 230V, 50 c/s mains. The frequency of instantaneous power consumed by the geyser is

  1. 25 c/s
  2. 50 c/s
  3. 100 c/s
  4. 150 c/s

Answer
Answer. c

15. A stove element draws 15A when connected to 230V line. How long does it take to consume one unit of energy?

  1. 3.45 h
  2. 2.16 h
  3. 1.0 h
  4. 0.29 h

Answer
Answer. d

16. Energy consumed by a heater of rating 1000 watts by operating it for a period of 2 hours will be

  1. 1 unit
  2. 2 unit
  3. 2.5 unit 
  4. 4 unit

Answer
Answer. b

17. A highly resistive material is chosen for the heating element in order to

  1. Reduce the length of the heating element
  2. Increase the life of the heating element
  3. Reduce the effect of oxidation
  4. Produce a large amount of current

Answer
Answer. a

18. In an electric room heat convector, the method of heating used is

  1. Arc heating
  2. Resistance heating
  3. Induction heating
  4. Dielectric heating

Answer
Answer. b

19. _________ heating method has a leading power factor.

  1. Resistance
  2. Dielectric
  3. Arc
  4. Induction

Answer
Answer. b

20. Which of the following in not a non-linear element?

  1. Transistor
  2. Heater coil
  3. Diode
  4. Electric arc with unlike electrodes

Answer
Answer. b

Pages: 1 2 3 4 5