Naked Science Forum
On the Lighter Side => Science Experiments => Topic started by: hamdani yusuf on 15/09/2023 05:26:25
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Wikipedia distinguishes capacitance into two different types, i.e. self capacitance and mutual capacitance.
https://en.wikipedia.org/wiki/Capacitance
Capacitance is the capability of a material object or device to store electric charge. It is measured by the charge in response to a difference in electric potential, expressed as the ratio of those quantities. Commonly recognized are two closely related notions of capacitance: self capacitance and mutual capacitance.[1]: 237?238 An object that can be electrically charged exhibits self capacitance, for which the electric potential is measured between the object and ground. Mutual capacitance is measured between two components, and is particularly important in the operation of the capacitor, an elementary linear electronic component designed to add capacitance to an electric circuit.
The capacitance between two conductors is a function only of the geometry; the opposing surface area of the conductors and the distance between them, and the permittivity of any dielectric material between them. For many dielectric materials, the permittivity, and thus the capacitance, is independent of the potential difference between the conductors and the total charge on them.
The SI unit of capacitance is the farad (symbol: F), named after the English physicist Michael Faraday. A 1 farad capacitor, when charged with 1 coulomb of electrical charge, has a potential difference of 1 volt between its plates.[2] The reciprocal of capacitance is called elastance.
Are they mutually exclusive to each other, without overlap?
Are there any other types of electric capacitance beside them?
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For a start, here's a video titled How Capacitors Work from National Maglab.
And this one from ElectroBoom, with the same title
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Measuring Human Body Capacitance (or any capacitance)
As I always say, AC hurts more than DC and the reason is human body capacitance. Let's see how big this capacitance is.
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There is only one, where c=q/v.
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There is only one, where c=q/v.
Maybe you can correct the Wikipedia article linked in the first post.
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Capacitance is simply the ability to hold charge, same as the volumetric capacity of an inflatable fluid container. Various methods of achieving this "capacitance" is what that wiki article is describing, NOT different types, as there is only one. Similarly one may find mention of self inductance and mutual inductance but there is only one inductance.
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Capacitance is simply the ability to hold charge, same as the volumetric capacity of an inflatable fluid container. Various methods of achieving this "capacitance" is what that wiki article is describing, NOT different types, as there is only one. Similarly one may find mention of self inductance and mutual inductance but there is only one inductance.
What is the more correct word to replace "type"?
Is there any other method?
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I've recorded the measurement of capacitance using a common digital multimeter which provide capacitance meter. The first video would describe the characteristics of the capacitance meter itself, like the frequency and voltage used.
Parallel plate capacitors have been described by many sources, including Wikipedia articles and Youtube videos. So I will be more focused on the electric capacitance of objects other than that, which are less known to most people.
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Before I uploaded my own video, I'd like to share an informative video measuring characteristics of a capacitor.
Capacitor self-resonance measured with an oscilloscope and signal generator - how to tutorial
This tutorial video shows how to estimate / measure the self-resonant frequency (SRF) of a capacitor using an oscilloscope and a signal generator.
The video also mentions some caveats to be aware of when attempting this. In addition to those mentioned in the video, there are more... The parasitic inductance of the fixture and probe should be substantially lower than the parasitics of the capacitor under test. For small RF capacitors, well under 1nF for example, this is especially important. Special RF fixtures would be needed to accurately measure the SRF.
There are several other factors that can influence this measurement, but the basic concept works well for capacitors used for DC bypassing, broadband signal coupling, etc. For RF applications, it is much more difficult to apply this method and get accurate results.
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Here's a flashy video demonstrating self capacitance.