The temperature of two bodies A and B are respectively `727^(@)C` and `327^(@)C` . The ratio `H_(A) : H_(B)` of the rates of heat radiated by them is

Options

A. `727:327`
B. `5:3`
C. `25 :9`
D. `625 :81`

Answer

D

Explanation

Heat energy radiated `propT^(4)`
According to Stenfan's law, the amount of heat energy (E) radiated per second by unit the area of a perfectly black body is directly proportional to the fourth power pf absolute temperature (T) of the body .
`"i.e "EpropT^(4)`
`therefore" " (H_(A))/(H_(B))=((273+727)/(273+327))^(4)=((1000)/(600))^(4)`
`=(625)/(81)`