Out of 100 kcal/second of incident radiant energy on the surface of a thermally transparent body, 300 kcal/second is reflected back. If the transmissivity of the body is 0.25, the emissivity of the surface will be_________________?

Related Mcqs:

Pick out the wrong statement ?

A. Heat transfer from a hot body to cold body by the emission of heat waves is called radiation B. Filmwise condensation takes place on non-wettable surfaces C. The boiling point of a solution is affected by liquid head as well as boiling point elevation D. None of these...

The equation, Nst = f/2, is the _____________ analogy?

A. Colburn B. Reynolds C. Prandtl D. None of these...

A perfect black body is a perfect _____________ of radiation?

A. Absorber B. Emitter C. Both A. & B. D. Neither A. nor B....

To reduce the tube side pressure drop for the same flow rate, the heat exchanger recommended is _______________?

A. 1-2 heat exchanger B. 1-1 heat exchanger C. 3-2 heat exchanger D. 2-4 heat exchanger...

Prandtl number for most of dry gases is about________________?

A. 0.001 B. 0.72 C. 70 D. 150...