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

Related Mcqs:

Unit of thermal conductivity in S.I. units is__________________?

A. J/m2 sec B. J/m °K sec C. W/m °K D. A. and C. above E. B. and C. above...

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

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

Film coefficient is defined as Inside diameter of tube________________?

A. Equivalent thickness of film B. Thermal conductivity Equivalent thickness of film Specific heat x Viscocity C. Thermal conductivity Molecular diffusivity of momentum Thermal diffusivity D. Film coefficient x Inside diameter Thermalconductivity E. none of the above...

According of Kirchhoff’s law______________________?

A. radiant heat is proportional to fourth power of absolute temperature B. emissive power depends on temperature C. emissive power and absorptivity are constant for all bodies D. ratio of emissive power to absorptive power is maximum for perfectly black body E. ratio of emissive power to absorptive power for all bodies is same and … According of Kirchhoff’s law______________________?Read More...

Log mean temperature difference in case of counter flow compared to parallel flow will be________________?

A. same B. more C. less D. depends on other factors E. none of the above...