Which Statement Below Regarding the First Law of Thermodynamics Is

question 27

Multiple Choice

Which statement below regarding the First Law of Thermodynamics is most correct?

• A) A system can do work externally only if its internal energy decreases.
• B) The internal energy of a system that interacts with its environment must change.
• C) No matter what other interactions take place, the internal energy must change if a system undergoes a heat transfer.
• D) The only changes that can occur in the internal energy of a system are those produced by non-mechanical forces.
• E) The internal energy of a system cannot change if the heat transferred to the system is equal to the work done by the system.

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Definitions:

Cross-Sectional Studies

Observational studies that analyze data from a population, or a representative subset, at a specific point in time.

Clinical Phase

A stage in the research and development process of new medical treatments that involves testing on human subjects to evaluate efficacy and safety.

Natural History

The course a disease takes in the absence of intervention, from its onset through its eventual resolution or progression to death.

Ultimate Outcome

The final or most significant result or consequence of a series of events or actions.