Answer:
In the given diagram Arrow Y indicates the second law of thermodynamics.
Explanation:
Second law of thermodynamics:
Total entropy of the system remains constant for an isolated system. If the amount of heat is converted into work there is loss of energy to the surrounding.
Arrow W:
It represent the work done by the piston for its movement. From second law of thermodynamic amount of heat is converted into work there is loss of energy to the surrounding.
This part doesn't represent the loss of heat to the surrounding. Thus, it do not indicate second law of thermodynamic.
Arrow Y:
It represent the heat added when work is done by the piston for its movement. From second law of thermodynamic amount of heat is converted into work there is loss of energy to the surrounding.
This part represents the absorption of heat to the surrounding. Thus, it indicates second law of thermodynamic.
Arrow Z:
It represent the work done by the piston for its movement. From second law of thermodynamic amount of heat is converted into work there is loss of energy to the surrounding.
This part doesn't represent the loss of heat to the surrounding. Thus, it do not indicate second law of thermodynamic.
Thus, only arrow Y indicates the second law of thermodynamics.
