- #1
jaumzaum
- 434
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- A cylinder with a gas inside moves with a velocity V. What would be the decrease in temperature caused by the sudden stop of the cylinder.
My solution:
Δ(kinetic energy) = Δε = mV²/2 = (3/2)nRΔT -> ΔT = MV²/3R
But the book solution is different
Δ(internal energy) = ΔU = mV²/2 = nℂvΔT -> ΔT = MV²/2ℂv
He considered mV²/2 to be the variation of internal energy istead of kinetic energy. As far as I know, the formula mv²/2 is for ε, not U. Am I wrong?
Which one is the correct solution?
[]'s
John
My solution:
Δ(kinetic energy) = Δε = mV²/2 = (3/2)nRΔT -> ΔT = MV²/3R
But the book solution is different
Δ(internal energy) = ΔU = mV²/2 = nℂvΔT -> ΔT = MV²/2ℂv
He considered mV²/2 to be the variation of internal energy istead of kinetic energy. As far as I know, the formula mv²/2 is for ε, not U. Am I wrong?
Which one is the correct solution?
[]'s
John