Entropy change in an inelastic collision.

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In an inelastic collision involving a 3 kg mass colliding with a stationary 9 kg mass, the change in entropy is questioned due to the lack of heat and temperature data. The formula ΔS = ΔQ/T is deemed unsuitable without these values. Instead, the discussion suggests using the entropy formula S = k ln(number of microstates) to find the difference in entropy before and after the collision. However, calculating the number of microstates for this system remains unclear, especially since kinetic energy is not conserved in inelastic collisions. The conversation highlights that while kinetic energy decreases, total energy remains conserved, prompting inquiry into the transformation of lost kinetic energy.
bbhill
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1. A 3 kg mass hits a stationary mass of 9 kg and sticks. What is the change in entropy?



So, I figure that I will need to \DeltaS = \DeltaQ/T.

However, I don't know the heat or the temperature of this reaction, so this couldn't possibly be the way to evaluate.

So, I think I could use S = k ln (number of microstates) and find the difference between the initial and final values of S. However, how would I calculate the number of microstates for this system?
 
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Inelastic collisions do not conserve kinetic energy. Here, the kinetic energy after the collision is less than before. However, total energy is always conserved. So, to what kind of energy is the lost kinetic energy transformed?
 
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