A hot metallic sphere of radius $r$ radiates heat. It's rate of cooling is
A hot metallic sphere of radius $r$ radiates heat. It's rate of cooling is
- A
Independent of $r$
- B
Proportional to $r$
- C
Proportional to ${r^2}$
- D
Proportional to $1/r$
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- [JEE MAIN 2021]
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