Suppose the sun expands, so that its radius becomes 100 times its present radius and its surface temperaturebecomes half its present value. The total energy emitted by it will increases by a factor of :

Suppose the sun expands, so that its radius becomes 100 times its pres

1.	Suppose the sun expands, so that its radius becomes 100 times its present radius and its surface temperaturebecomes half its present value. The total energy emitted by it will increases by a factor of :
Answer» 16 625 256 1000 Solution :According to Stefan.s LAW, total energy RADIATED by sun per unit time is `E=sigmaT^(4)A=sigmaT^(4).4piR^(2)` `:.(E_(2))/(E_(1))=((T_(2))/(T_(1)))^(4).((R_(2))/(R_(1)))^(2)=(((T)/(2))/(T))^(4).((100)/(R))^(2)` `=(1)/(16)xx1000` `E_(2)=625E_(1)` correct CHOICE is (b).

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