Question

A black body at 2:27 degree celsius radiates heat @ 7 calories per cm square second at a temperature of

Answer 1

Applying Stefans law of radiation, E = σ T4

Hence, E1 / E2 = (T1 / T2)4

E2 = E1 (T2 / T1)4

   = 7 [ (727 + 273) / (227 + 273)]4 = 7 (1000/500)4 = 112 cal/cm2/s

Answer 2

All objects emit electromagnetic radiation according to their temperature. A black body is an idealized object that absorbs all electromagnetic radiation