Thermocouple in a thermal well behaves as a true ________________?

Related Mcqs:

1. The calibration data of a thermocouple with its cold junction at 0°C are given below. The hot junction of the thermocouple is placed in a bath at 80°C, while its cold junction is at 20°C. What is the emf of thermocouple ?

   A. 3.26 mv
   B. 0.80 mv
   C. 2.46 mv
   D. 2.43 mv

2. Emf developed by a thermocouple while measuring a temperature of 800°C is about 31 mV. The type of thermocouple used is________________?

   A. Chromel-alumel
   B. Iron-constantan
   C. Platinum-platinum + rhodium
   D. None of these

3. Emf developed by a thermocouple while measuring a temperature of 400°C is 22 mV. The type of thermocouple used is ___________________?

   A. Chromel-alumel
   B. Iron-constantan
   C. Platinum-rhodium
   D. Platinum-platinum + rhodium

4. Emf developed by a thermocouple, while measuring a temperature of 600°C is about 5.5 mV. The type of thermocouple used is_______________?

   A. Chromel-alumel
   B. Iron-constantan
   C. Platinum-platinum + rhodium
   D. Either A., B. or C.

5. Thermal conductivity based continuous flue gas analyser makes use of varying thermal conductivity of the constituents of flue gases. Which of the following constituents of flue gases has the maximum thermal conductivity ?

   A. CO2
   B. N2
   C. O2
   D. CO

6. Working principle of bimetallic thermometers is difference in linear co-efficient of thermal expansion of two strips of different metals welded together. Which of the following has the maximum thermal co-efficient of linear expansion ?

   A. Nickel
   B. Brass
   C. Chromel
   D. Invar

7. Nickel percentage in invar which is an iron-nickel alloy, and is used as a thermocouple material is __________________?

   A. 12
   B. 36
   C. 54
   D. 68

8. The temperature of tempering oil baths maintained at 400°C during heat treatment of steel is measured by a/an _____________ thermocouple?

   A. Chromel-alumel
   B. Iron-constantan
   C. Platinum-platinum/rhodium
   D. None of these

9. Out of the following thermocouple wire insulating material, the highest temperature rating is for________________?

   A. Teflon
   B. Ceramic fibre
   C. Asbestos
   D. Fibre glass

10. Which of the following relates the absorption & evolution of heat at the junctions of a thermocouple to the current flow in the circuit ?

    A. Seebeck effect
    B. Peltier effect
    C. Joule heating effect
    D. Thomson effect