NEET Questions Solved

NEET - 2009

A black body at 227°C radiates heat at the rate of 7 cal cm-2s-1. At a temperature of 727°C, the rate of heat radiated in the same units will be 

(a) 60                                      (b) 50

(c) 112                                    (d) 80

 Apply Stefan's law of radiation.

           E=σT4

           E1E2=T1T24

         E2=7273+727273+2274

               =10005004×7

              =112calcm-2s-1

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