Question

Which of the following is incorrect regarding the first law of thermodynamics?

• A. It introduces the concept of internal energy
• B. It introduces the concept of entropy
• C. It is applicable to any cyclic process
• D. It is a restatement of the law of conservation of energy

Hint:

Remember, the first law is about energy conservation and internal energy. The second law introduces entropy, which is related to the disorder and irreversibility of natural processes.

Answer 1

The Correct Option is B

The first law of thermodynamics states:

\[ \Delta Q = \Delta U + \Delta W \] 
Where: 
- \( \Delta Q \) is the heat supplied to the system, 
- \( \Delta U \) is the change in internal energy, 
- \( \Delta W \) is the work done by the system. 
The first law introduces the concept of internal energy and explains how energy is conserved in the system. It is essentially a restatement of the law of conservation of energy.

However, the concept of entropy is not introduced by the first law but by the second law of thermodynamics, which deals with the direction of processes and the measure of disorder in the system. Therefore, the statement in option (2) is incorrect.