About Second Law of Thermodynamics

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If a hot object did not emit radiation, it would violate the second law of thermodynamics by allowing heat to flow from a cooler body to itself without external work. The second law dictates that heat transfer occurs naturally from hot to cold, increasing entropy. A hot body emits more radiation than it absorbs in a closed system, maintaining thermodynamic balance. If a hot object could absorb radiation but not emit it, it would gain heat from a cooler object, contradicting thermodynamic principles. A perfect white body reflects radiation without absorption or emission, thus not violating thermodynamic laws.
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Why if a hot object did not emit radiation then second law of thermodynamics would be violated?
 
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fxdung said:
Why if a hot object did not emit radiation then second law of thermodynamics would be violated?
Every body in the universe emits and absorbs radiation.As far as heat flow is considered it takes place in the direction of hotter to colder body if no external work is done .The 2nd Law of Thermodynamics basically gives the direction of natural(irreversible) process which is the increase in entropy.so your hot body will radiate more than it absorbs if no work is done externally.
 
fxdung said:
Why if a hot object did not emit radiation then second law of thermodynamics would be violated?
If a hot object did not emit radiation but could nonetheless absorb radiation then it would gain heat from a cooler body that did radiate. That would be a 2nd law violation.
 
fxdung said:
Why if a hot object did not emit radiation then second law of thermodynamics would be violated?
A perfect white body does not violate thermodynamics. It would neither emit nor absorb any radiation, but simply reflect it.
 
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