Timeline for How to convince myself that capacitance cannot be a function of voltage?
Current License: CC BY-SA 4.0
9 events
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| S Oct 15, 2020 at 14:33 | history | suggested | Sebastiano | CC BY-SA 4.0 |
Improved mathjax code
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| Oct 15, 2020 at 14:32 | review | Suggested edits | |||
| S Oct 15, 2020 at 14:33 | |||||
| Oct 9, 2020 at 13:32 | comment | added | Roger V. | @SolomonSlow I am talking here about a capacitance as it is understood in theoretical physics - e.g., Landau&Livshits' Electrodynamics of continuous media defines capacitance of a system of conductors as an expansion coefficient of their energy. This is how many quantities are rigorously defined. I agree, that this is rather different from the definitions in basic physics or engineering. Just like Lagrangian and Hamiltonian mechanics looks very different from Newton' laws that we study in school. | |
| Oct 9, 2020 at 13:18 | comment | added | Solomon Slow | The capacitance of an ideal capacitor is constant by definition. The capacitance of a practical capacitor is what it is. We talk about ideal capacitors (and other ideal components) because they obey simple mathematical laws which usually are "close enough" to the actual behavior of practical components that we can ignore the difference. But as the "Varicap" answers here point out, not all practical components are so nicely behaved. | |
| Oct 9, 2020 at 12:21 | comment | added | Roger V. | In principle, yes - by one often considers systems which are, overall, electrically neutral. For example, an electric circuit is electrically neutral, but there may be dis-balance of charge on the capacitor plates (one has $+Q$, the other $-Q$). | |
| Oct 9, 2020 at 11:07 | comment | added | user249968 | Thank you, sir! Understood. I have an extra question: In the Taylor series of $Q(V)$ can $Q(0)$ be a non-zero entity (assuming that potential is zero at infinity). | |
| Oct 9, 2020 at 10:50 | vote | accept | CommunityBot | moved from User.Id=249968 by developer User.Id=76591 | |
| Oct 9, 2020 at 9:35 | history | edited | Roger V. | CC BY-SA 4.0 |
added 102 characters in body
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| Oct 9, 2020 at 9:29 | history | answered | Roger V. | CC BY-SA 4.0 |