Two identical metal balls at temperature `200^(@)C` and `400^(@)C` kept in air at `27^(@)C`. The ratio of net heat loss by these bodies isA. `1//4`B. `1//2`C. `1//16`D. `(473^(4) - 300^(4))/(673^(4) - 300^(4))`

Two identical metal balls at temperature `200^(@)C` and `400^(@)C` kep

1.	Two identical metal balls at temperature `200^(@)C` and `400^(@)C` kept in air at `27^(@)C`. The ratio of net heat loss by these bodies isA. `1//4`B. `1//2`C. `1//16`D. `(473^(4) - 300^(4))/(673^(4) - 300^(4))`
Answer» Correct Answer - D If temperature of surrounding is considered, then net loss of energy of a body by radiation `Q = A epsilon(T^(4)-T_(0)^(4)) rArr Q prop (T^(4)-T_(0)^(4))` `=(Q_1)/(Q_2) = (T_(1)^(4)-T_(0)^(4))/(T_(2)^(4)-T_(0)^(4))` `=((273+200)^(4)-(273+27)^(4))/((273+400)^(4)-(273+27)^(4))` `=((473)^(4)-(300)^(4))/((673)^(4)-(300)^(4))` .

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Two identical metal balls at temperature `200^(@)C` and `400^(@)C` kept in air at `27^(@)C`. The ratio of net heat loss by these bodies isA. `1//4`B. `1//2`C. `1//16`D. `(473^(4) - 300^(4))/(673^(4) - 300^(4))`

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