A black metal foil is warmed by radiation from a small sphere at temperature ‘T′ and at a distance ‘d′. It is found that the power received by the foil is P. If both the temperature and distance are doubled, the power received by the foil will be :

A black metal foil is warmed by radiation from a small sphere at tempe

1.	A black metal foil is warmed by radiation from a small sphere at temperature ‘T′ and at a distance ‘d′. It is found that the power received by the foil is P. If both the temperature and distance are doubled, the power received by the foil will be :
Answer» A black metal foil is warmed by radiation from a small sphere at temperature $‘ T^{'}$ and at a distance $‘ d^{'}$ . It is found that the power received by the foil is $P$ . If both the temperature and distance are doubled, the power received by the foil will be :

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A black metal foil is warmed by radiation from a small sphere at temperature ‘T′ and at a distance ‘d′. It is found that the power received by the foil is P. If both the temperature and distance are doubled, the power received by the foil will be :

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