Practice question · Multiple choice
A partial derivative holds all other variables constant. Why is that physically meaningful rather than an artificial restriction?
Hints
- Ask how you would measure how pressure depends on temperature.
- What do you do with the volume while you measure?
Show the answer
B. Because experiments are designed the same way: vary one factor
Why
Holding variables fixed is exactly experimental control. The total derivative then reassembles the pieces when everything varies together, which is what the chain rule does.
Practise Partial Derivatives
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