Question

The diagram shows an engine piston before and after heat is added, which illustrates the laws of thermodynamics.

An illustration of two vertical cylinders. The one has the piston farther into the cylinder labeled W with an arrow pointing downwards on the piston labeled air pressure. The second has the piston just in the cylinder with the bottom of the cylinder red labeled heat added labeled Y and an arrow up as well as an arrow up the piston labeled Z and work Done.

Which arrow best indicates the second law of thermodynamics?
W
X
Y
Z

Answer 1

In the above diagram, The arrow that best indicates the second law of thermodynamics in the diagram is option c: Y.

The second law of thermodynamics states that the total entropy of an isolated system always increases over time. Entropy is a measure of the disorder of a system. When heat is added to a system, it increases the disorder of the system, and therefore increases the entropy.

The other arrows in the diagram do not represent the second law of thermodynamics. These arrows indicate the transfer of energy between the system and its surroundings, but they do not say anything about the entropy of the system.

Therefore, the only arrow that best indicates the second law of thermodynamics is arrow Y.