Power is the energy transferred or "WORK DONE" in one second
Here stress is parallel to the surface of the body. So it's a Shear stress.
Answer:
The entropy of a gas increases when it expands into a vacuum because the number of possible states increases .
Explanation:
When a gas expand in a vacuum, the molecules of the gases vibrates very fast and starting moving with higher velocity in random directions which means the level of disorder in the gases increases.
Now the possible state of the gas molecule increases such as the particle can be located at different position due to increased randomness.
<u>Entropy is the measure of this randomness and thus with this increased randomness entropy also increases.</u>
