Thermal diffusivity of a substance is __________________?

Related Mcqs:

1. 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...

2. 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...

3. Unit of thermal diffusivity is_________________?

   A. m2/hr B. m2/hr°C C. kcal/m2 hr D. kcal/m.hr°C E. kcal/m2 hr°C...

4. 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...

5. Thermal conductivity of solid metals with rise in temperature normally___________________?

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

6. 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...

7. Thermal conductivity of air with rise in temperature__________________?

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

8. Thermal conductivity of water at 20°C is of the order of_____________________?

   A. 0.1 B. 0.23 C. 0.42 D. 0.51 E. 0.64...

9. The ratio of heat flow Q1/Q2 from two walls of same thickness having their thermal conductivities as ATj – 2K2 will be ________________?

   A. I B. 0.5 C. 2 D. 0.25 E. 4.0...

10. Thermal conductivity of wood depends on_______________?

    A. moisture B. density C. temperature D. all of the above E. none of the above...