A black body is heated from 270C to 1270C. The ratio of their energies of radiation emitted will be

From Stefan's law, the total radiant energy emitted per second per unit surface area of a black body is proportional to the fourth power of the absolute temperature of the body.That is E = σT4where σ is Stefan's constantGiven,initial temperature T1 = 273 + 27 = 300 Kfinal temperature T2  = 127 + 273 = 400 KHence, we have    E1E2= T14T24 = (300)4(400)4 = 81256Therefore, E1 : E2 = 81 : 256