According to Stefan-Boltzmann law, ideal radiators emit radiant energy at a rate proportional to___________________?

Related Mcqs:

1. Stefan Boltzmann law is applicable for heat transfer by __________________?

   A. conduction B. convection C. radiation D. conduction and radiation combined E. convection and radiation combined...

2. 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...

3. According to Stefan’s law, the total radiation from a black body per second per unit area is proportional to____________________?

   A. absolute temperature B. T2 C. T5 D. t E. l/T...

4. 40% of incident radiant energy on the surface of a thermally transparent body is reflected back. If the transmissivity of the body be 0.15, then the emissivity of surface is____________________?

   A. 0.45 B. 0.55 C. 0.40 D. 0.75 E. 0.60...

5. According to Wien’s law, the wavelength corresponding to maximum energy is proportion to ________________?

   A. absolute temperature (T) B. I2 C. f D. t E. 1/r...

6. The energy distribution of an ideal reflector at higher temperatures is largely in the range of ___________________?

   A. shorter wavelength B. longer wavelength C. remains same at all wavelengths D. wavelength has nothing to do with it E. none of the above...

7. The ratio of the energy absorbed by the body to total energy falling on it is called_________________?

   A. absorptive power B. emissive power C. absorptivity D. emissivity E. none of the above...

8. The rate of energy emission from unit surface area through unit solid angle, along a normal to the surface, is known as ________________?

   A. emissivity B. transmissivity C. reflectivity D. intensity of radiation E. absorptivity...

9. According to Kirchoff’s law, the ratio of emissive power to absorptivity for all bodies is equal to the emissive power of a _________________?

   A. grey body B. brilliant white polished body C. red hot body D. black body E. none of the above...

10. Planck’s law holds good for________________?

    A. black bodies B. polished bodies C. all coloured bodies D. all of the above E. none of the above...