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Page: technics-electrical-engineering-capacitor_en.htm

Date: 2020.12.23 17:55:41 (UTC+1)

Name: Alexander Chen

Comment:

For equation [3.5], I see that you've used Calculus to anti-differentiate the equation

You took [3.4] and you anti-differentiated each side with dU.

But why? Why is U not constant? What about the other parts of 3.4? Are THEY constant as well?

Me: If you have two conductive plates with a given area and a given distance, U will increase the more charge you "pump" from one side to the other. Thats simply the physics you can measure. All variables are constant as long as you don't move charges. If you do so (either by "pumping" or by discharging the capacitor) the values will change.