Depending on the radiating properties, a body will be black when_________________?
A. p = 0, x = 0 and a = 1
B. p= l,T = 0anda = 0
C. p = 0, x = 1 and a = 0
D. x = 0, a + p = 0
E. a = 0,x + p= 1.
where a = absorptivity, p ==…
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____________________?
Absorptivity of a body will be equal to its emissivity___________________?
A. at all temperatures
B. at one particular temperatureC. when system is under thermal equi-librium
D. at critical temperature
E. for a polished body…
Two plates spaced 150 mm apart are maintained at 1000°C and 70°C. The heat transfer will take place mainly by ___________________?
B. free convection
C. forced convectionD. radiation
E. radiation and convection…