If a system absorbs 100 J of heat and does 40 J of work, what is the change in i
Practice Questions
Q1
If a system absorbs 100 J of heat and does 40 J of work, what is the change in internal energy?
60 J
40 J
100 J
140 J
Questions & Step-by-Step Solutions
If a system absorbs 100 J of heat and does 40 J of work, what is the change in internal energy?
Correct Answer: 60 J
Step 1: Identify the amount of heat absorbed by the system. In this case, it is 100 J.
Step 2: Identify the amount of work done by the system. In this case, it is 40 J.
Step 3: Recall the formula from the first law of thermodynamics: ΔU = Q - W.
Step 4: Substitute the values into the formula: ΔU = 100 J - 40 J.
Step 5: Perform the subtraction: 100 J - 40 J = 60 J.
Step 6: Conclude that the change in internal energy (ΔU) is 60 J.
First Law of Thermodynamics – The principle that the change in internal energy (ΔU) of a system is equal to the heat added to the system (Q) minus the work done by the system (W).