Thermal diffusivity is ____________________? - PakMcqs

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. 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...

3. Thermal diffusivity of a substance is __________________?

   A. directly proportional to thermal con¬ductivity B. inversely proportional to density of substance C. inversely proportional to specific heat D. all of the above E. none of the above...

4. 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...

5. 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...

6. Unit of thermal conductivity in M.K.S. units is ___________________?

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

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. Which of the following is expected to have highest thermal conductivity_______________?

   A. steam B. solid ice C. melting ice D. water E. boiling water...

9. Thermal conductivity of glass-wool varies from sample to sample because of variation in ________________ ?

   A. composition B. density C. porosity D. structure E. all of the above...

10. The thermal diffusivities for gases are generally_____________________?

    A. more than those for liquids B. less than those for liquids C. more than those for solids D. dependent on the viscosity E. same as for the liquids...