Based on a diagram showing heat being absorbed by a system and work being done on the system, does this represent an increase or decrease in the internal energy of the system?

• A. Increase in internal energy
• B. No change in internal energy
• C. Decrease in internal energy

Answer: (A)

Verified step by step guidance

1. Recall the first law of thermodynamics, which states that the change in internal energy of a system (\(\Delta U\)) is given by the equation: \(\Delta U = Q + W\) where \(Q\) is the heat absorbed by the system and \(W\) is the work done on the system.
2. Identify the signs of \(Q\) and \(W\) based on the problem description: - Heat being absorbed by the system means \(Q\) is positive. - Work being done on the system means \(W\) is positive.
3. Substitute the positive values of \(Q\) and \(W\) into the equation \(\Delta U = Q + W\). Since both are positive, their sum will be positive.
4. A positive \(\Delta U\) indicates that the internal energy of the system increases.
5. Therefore, based on the diagram showing heat absorbed and work done on the system, the internal energy of the system increases.