Heat TransferHard
Question
Two electric lamps A and B radiate the same power. Their filaments have the same dimensions and have emissivities eA and eB. Their surface temperatures are TA and TB The ratio
will be equal to :-
Options
A.
B.
C.
D.
Solution
The power radiated by a filament is P = e(σT4) (area), where e = emissivity, σ = Stefan′s constant, T = surface temperature. Here, eT 4 = constant or
eATA4 = eBTB4
eATA4 = eBTB4
Create a free account to view solution
View Solution FreeMore Heat Transfer Questions
2 gms steam at 100o C is mixed with 5 gm ice at - 40oC in an ideal calorimeter. The final temperature of the system will...The radii is of two spheres made of same metal are r and 2r. These are heated to the same temperature and placed in the ...A black body is at a temperature of 5760 K. The energy of radiation emitted by the body at wavelength 250nm is U1, at wa...One end of a thermally insulated rod is kept at a temperature T1 and the other at T2. The rod is composed of two section...Temperature of a body is 4000 C assuming the surrounding themperature to be negligible at what tempearture will be the b...