If 'Q' is the amount of heat supplied to a system and 'W' is the work done, then change in internal energy can be defined as:
Correct answer: B. Q - W
- A. Q/W
- B. Q - W
- C. W/Q
- D. 1 + Q/W
Explanation
The 1st law of thermodynamics is given by the equation:∆Q=∆U+∆W Where,∆Q is the heat supplied to the system ∆U is the change in internal energy of the system ∆W is the work done by the system. To derive the equation for change in internal energy, we can rearrange the above equation as follows:∆U = ∆Q - ∆WThis equation tells us that the change in internal energy of the system (∆U) is equal to the heat supplied to the system (∆Q) minus the work done by the system (∆W).
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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.
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