About Second Law of Thermodynamics

In summary, the second law of thermodynamics states that heat flow occurs from hotter to colder bodies without any external work, leading to an increase in entropy. Therefore, if a hot object did not emit radiation, it would violate this law. However, a perfect white body, which reflects radiation instead of emitting or absorbing it, would not violate the law.
  • #1
fxdung
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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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  • #2
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.
 
  • #3
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.
 
  • #4
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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What is the Second Law of Thermodynamics?

The Second Law of Thermodynamics is a fundamental law of physics that states that the total entropy of a closed system will always increase over time. This means that in any process, some energy will inevitably be lost as heat and cannot be recovered.

Why is the Second Law of Thermodynamics important?

The Second Law of Thermodynamics is important because it explains why certain processes, such as energy conversion, are irreversible. It also has a wide range of applications, from the efficiency of engines to the behavior of chemical reactions.

How does the Second Law of Thermodynamics relate to entropy?

Entropy is a measure of the disorder or randomness in a system. The Second Law of Thermodynamics states that entropy will always increase in a closed system, meaning that the system will become more disordered over time.

Can the Second Law of Thermodynamics be violated?

No, the Second Law of Thermodynamics is a fundamental law of nature and cannot be violated. It has been extensively tested and has never been found to be incorrect.

What is an example of the Second Law of Thermodynamics in action?

An example of the Second Law of Thermodynamics is the process of boiling water on a stovetop. As heat is applied, the water molecules become more chaotic and disordered, increasing the entropy of the system. This process cannot be reversed, as the energy lost as heat cannot be fully recovered.

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