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thomasj
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Is there any electrostatic field around the leads of a charged capacitor? Let's take just the negative one. If I take a piece of tissue and put close to that terminal it will attract or repel the paper? And if not, why?
Just to add to the good reply by @kuruman -- The force would depend on the amount of charge on the tissue and the capacitance between the tissue and the lead. That capacitance depends on the areas of the tissue and the lead, and the separation between them.thomasj said:If I take a piece of tissue and put close to that terminal it will attract or repel the paper?
kuruman said:Of course, most of the charge will be distributed on the inner surface of the capacitor plates which means that the electric field is by far strongest between the plates.
I don't understand what you mean by this.thomasj said:Are you sure the inner field doesn't hold down all of e- and p+ force?
The two capacitor plates have the bulk of the electric field energy between them, yes, but the two leads outside the capacitor still have a small parasitic capacitance between them, and they have the same voltage Vc between them that the plates inside the capacitor have.thomasj said:Are you sure the inner field doesn't hold down all of e- and p+ force?
If you have 1V between two objects that are 1mm apart, the electric field (E-field) between them will be 1V/0.001m = 1000 V/m.thomasj said:But how can I calculate something? Voltage vs. field strength at 1mm from the lead for example.
I mean: why field strength stronger between the plates? Electron and proton are point charges, field is like a bubble around them. Half of the strength between the plates is on each terminal, isn't it?kuruman said:I don't understand what you mean by this.
And how much is that? Can you compare with something?berkeman said:If you have 1V between two objects that are 1mm apart, the electric field (E-field) between them will be 1V/0.001m = 1000 V/m.
Uh, OK, I understand. But what if I connect that lead to a larger plate, an aluminum foil for example?berkeman said:What is the spacing of the plates compared to the spacing of the leads? Are you familiar with the formula for capacitance in terms of plate area and spacing?
Then you will have a capacitor with a new capacitance that will depend on the size, shape and position of the foil. Capacitance is a quantity that depends only on the geometry of the two conductors.thomasj said:Uh, OK, I understand. But what if I connect that lead to a larger plate, an aluminum foil for example?
The Potential Difference between the terminals and between the plates is the same. The FIELD (Volts per metre) is a lot higher between the plates because the spacing is very small.thomasj said:Are you sure the inner field doesn't hold down all of e- and p+ force?
A capacitor is an electronic component that is used to store electrical energy in the form of an electrostatic field.
A capacitor works by having two conductive plates separated by an insulating material, also known as a dielectric. When a voltage is applied to the plates, an electrostatic field is created between them, storing electrical energy.
Capacitance is the measure of a capacitor's ability to store electrical energy. It is an important factor in determining the behavior of a circuit, as it affects the flow of current and voltage in the circuit.
A capacitor and a battery both store electrical energy, but they do so in different ways. A capacitor stores energy in the form of an electrostatic field, while a battery stores energy in the form of a chemical reaction. Additionally, capacitors can release their energy quickly, while batteries release their energy slowly over time.
The capacitance of a capacitor can be calculated by dividing the charge on one plate by the potential difference between the two plates. It can also be calculated by multiplying the permittivity of the dielectric material by the area of the plates and dividing by the distance between them.