Temperature of steam at around 540°C can be measured by ____________________?

Related Mcqs:

1. Thermal conductivity of water in general with rise in temperature ____________________?

   A. increases
   B. decreases
   C. remains constant
   D. may increase or decrease depending on temperature
   E. none of the above

2. A steam pipe is to be insulated by two insulating materials put over each other . For best results__________________?

   A. better insulation should be put over pipe and better one over it
   B. inferior insulation should be put over pipe and better one over it
   C. both may be put in any order
   D. whether to put inferior OIL over pipe or the better one would depend on steam temperature
   E. unpredictable

3. Thermal diffusivity of a substance is ____________________?

   A. proportional of thermal conductivity
   B. inversely proportional to k
   C. proportional to (k)
   D. inversely proportional to k2
   E. none of the above

4. Thermal diffusivity is ____________________?

   A. a dimensionless parameter
   B. function of temperature
   C. used as mathematical model
   D. a physical property of the material
   E. useful in case of heat transfer by radiation

5. The unit of Stefan Boltzmann constant is ____________________?

   A. watt/cm2 °K
   B. watt/cm4 °K
   C. watt2/cm °K4
   D. watt/cm2 °K4
   E. watt/cm2 °K2

6. Thermal conductivity of non-metallic amorphous solids with decrease in temperature __________________?

   A. increases
   B. decreases
   C. remains constant
   D. may increase or decrease depending on temperature
   E. unpredictable

7. Thermal conductivity of air at room temperature in kcal/m hr °C is of the order of__________________?

   A. 0.002
   B. 0.02
   C. 0.01
   D. 0.1
   E. 0.5

8. Heat conducted througfi unit area and unit thick face per unit time when temperature difference between opposite faces is unity,is called__________________?

   A. thermal resistance
   B. thermal coefficient
   C. temperature gradient
   D. thermal conductivity
   E. heat-transfer

9. Two balls of same material and finish have their diameters in the ratio of 2 : 1 and both are heated to same temperature and allowed to cool by radiation. Rate of cooling by big ball as compared to smaller one will be in the ratio of____________________?

   A. 1 :1
   B. 2: 1
   C. 1 : 2
   D. 4 : 1
   E. 1 : 4

10. If the temperature of a solid surface changes form 27°C to 627°C, then its emissive power changes in the ratio of___________________?

    A. 3
    B. 6
    C. 9
    D. 27
    E. 81