A system can be taken from the initial state P1V1 to the final state P2V2 by two different methods. Let Q and W represent the heat given to the system and the work done by the system.Which of the following must be the same in both the methods?
Correct answer: D. Q - W
- A. Q
- B. W
- C. Q + W
- D. Q - W
Explanation
Internal energy would be the same irrespective of the path.U (internal energy) = Q - W
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About First Law of Thermodynamics
The first law relates heat supplied, work done and the change in internal energy through energy conservation. Problems use sign conventions and apply the law to isothermal, adiabatic, isobaric and isochoric processes. Internal energy is a state function, while heat and work depend on the path followed.
Practise Thermodynamics
714 free Thermodynamics MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More First Law of Thermodynamics questions
Heat and work are equivalent. This means
If heat energy of 100 J is taken out but 400 J work is done on the system, the change in internal energy is:
During adiabatic compression work done is equal to 200 J. What will be the change in internal energy?
When 20J of work was done on a gas, 40J of heat energy was released If the initial internal energy of the gas was 70J. what is the final internal energy?
A carnot engine working between 200k and 400k has a work output of 600 J per cycle. How much heat energy is supplied to the engine from the source of each cycle.
During each cycle, a heat engine with an efficiency of 25% takes in 800J of energy. How much waste heat energy is expelled in each cycle?