Reversibility of evaporating ice ball

AI Thread Summary
The discussion centers on the reversibility of an ice ball evaporating upon impact with a wall. It is established that the process is not reversible due to the increase in entropy, as water vapor cannot spontaneously condense and freeze back into an ice ball with velocity. Participants seek a more concrete explanation beyond qualitative reasoning, referencing the second law of thermodynamics and Clausius's principles. The conversation highlights that the forward process converts mechanical energy into internal energy, raising questions about the feasibility of the reverse process occurring spontaneously. Ultimately, the consensus is that the irreversible nature of this scenario aligns with thermodynamic laws.
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Homework Statement



A ball of ice is thrown against a wall with such as speed than the ball of ice evaporates. Is this process reversible?

Homework Equations



if entropy doesn't change, process is reversible.

The Attempt at a Solution



I'm pretty darn sure the answer is no, but I am looking for qualitative reasons as to why this is not reversible.

When my teacher went over reversibility, he said we should just run the process in (time) reverse and see if it makes sense.

This situation does not make sense to me in reverse; water vapor will not spontaneously condense and freeze into an ice-ball that has some velocity.


Can anyone offer a more concrete line of reasoning other than "this process doesn't make sense in reverse".
 
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That's a fairly good qualitative description of irreversibility.

One that's a bit more quantitative, how did Clausius characterize about the second law of thermodynamics?
 
Since the forward process involves converting mechanical energy entirely into internal energy of the snow ball (ignoring any heating of the wall, air etc.), what would the reverse process involve? Following up on DH's suggestion, does the second law permit such a process to occur spontaneously?

AM
 
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