Electric heating and heating methods - Electrical Engineering (MCQ) questions and answers

1)   A good heating element should have

a. High resistivity and low melting point
b. Low resistivity and high melting point
c. High resistivity and high melting point
d. Low resistivity and low melting point
Answer  Explanation 

ANSWER: High resistivity and high melting point

Explanation:
No explanation is available for this question!


2)   Eureka is an alloy of

a. Nickel and chromium
b. Nickel and copper
c. Iron, chromium and aluminium
d. Nickel, chromium and aluminium
Answer  Explanation 

ANSWER: Nickel and copper

Explanation:
No explanation is available for this question!


3)   In salt bath heating, the current are allowed to flow only through the

a. Only through the salt bath
b. Only through the material being heated
c. Through both (a) and (b)
d. None of these
Answer  Explanation 

ANSWER: Only through the salt bath

Explanation:
No explanation is available for this question!


4)   Direct resistance heating method is used in

a. Salt bath furnaces
b. Resistance welding
c. Electrode boiler for heating water
d. All of these
Answer  Explanation 

ANSWER: All of these

Explanation:
No explanation is available for this question!


5)   The sun’s rays reach the earth without heating the atmosphere, this is due to

a. Convection
b. Radiation
c. Conduction
d. None of these
Answer  Explanation 

ANSWER: Radiation

Explanation:
No explanation is available for this question!


6)   In radiation mode of heat transfer, the heat is transferred from one body to other

a. From molecule to molecule due to the temperature gradient between two parts
b. By actual movement of the heated molecules
c. Without actually heating the medium in between
d. All of these
Answer  Explanation 

ANSWER: Without actually heating the medium in between

Explanation:
No explanation is available for this question!


7)   The heat can be transferred from high temperature body to low temperature body by

a. Conduction method
b. Convection method
c. Radiation method
d. All of these
Answer  Explanation 

ANSWER: All of these

Explanation:
No explanation is available for this question!


8)   The efficiency of heating is more for

a. Solid fuels
b. Oil heating
c. Gas heating
d. Electric heating
Answer  Explanation 

ANSWER: Electric heating

Explanation:
No explanation is available for this question!