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Question
Mark the correct options:
- A system X is in thermal equilibrium with Y but not with Z. System Y and Z may be in thermal equilibrium with each other.
- A system X is in thermal equilibrium with Y but not with Z. Systems Y and Z are not in thermal equilibrium with each other.
- A system X is neither in thermal equilibrium with Y nor with Z. The systems Y and Z must be in thermal equilibrium with each other.
- A system X is neither in thermal equilibrium with Y nor with Z. The system Y and Z may be in thermal equilibrium with each other.
Solution
b and d
Explanation:
Two bodies are said to be in thermal equilibrium with each other when no heat flows from one body to the other. That is when both bodies are at the same temperature.
According to the problem,
b. If two systems X and Y are in thermal equilibrium, i.e., Tx = Ty, and x is not in thermal equilibrium with z, .ie, Tx ≠ Tz then clearly, Ty ≠ Tz. Hence, y and z are not in thermal equilibrium.
d. If X is not in thermal equilibrium with Y, i.e, Tx ≠ Ty and also X is not in thermal equilibrium with Y, i.e., Tx ≠ Tz. Then we cannot say about the equilibrium of Y and Z, they may or may not be in equilibrium.
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