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# Parallel plate capacitor watch

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1. I know when two parallel plates connected in a circuit electrons flow off one plate and onto the other giving each plate opposite charges, but why does this happen? Also why is it necessary that the plates are parallel and close to each other?
2. (Original post by MEPS1996)
I know when two parallel plates connected in a circuit electrons flow off one plate and onto the other giving each plate opposite charges, but why does this happen? Also why is it necessary that the plates are parallel and close to each other?
When connected in a circuit with a power source and they are initially uncharged plates, each plate is charged to an equal but opposite charge. This is because the electrons flow from the negative terminal on the battery to one plate, making this plate negative, but this then repels the electrons on the other plate away to the other terminal of the battery making this plate positively charged. In between the plates there is an insulating material (a dielectric) so that charge doesn't flow between them (as you seemed to think). There is subsequently a potential difference between the plates due to difference in charge as V=E/Q. I

It is necessary dor the plates to br close so that the electrons on the plates can repel each other.

I am not entirely sure why the are parallel, but I think it's again to do with the electrons repelling each other symmetrically so that it is equal but opposite charged plates.

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3. (Original post by RATKING)
When connected in a circuit with a power source and they are initially uncharged plates, each plate is charged to an equal but opposite charge. This is because the electrons flow from the positive terminal on the battery to one plate, making this plate negative, but this then repels the electrons on the other plate away to the other terminal of the battery making this plate positively charged. In between the plates there is an insulating material (a dielectric) so that charge doesn't flow between them (as you seemed to think). The plates finally reach a dynamic equilibrium. There is subsequently a potential difference between the plates due to difference in charge as V=E/Q. I

It is necessary dor the plates to br close so that the electrons on the plates can repel each other.

I am not entirely sure why the are parallel, but I think it's again to do with the electrons repelling each other symmetrically so that it is equal but opposite charged plates.

Posted from TSR Mobile
thanks a lot ratking.
4. (Original post by MEPS1996)
thanks a lot ratking.
No problem, it was revision fot myself anyway. Had to tjink before I posted !
5. (Original post by RATKING)
When connected in a circuit with a power source and they are initially uncharged plates, each plate is charged to an equal but opposite charge. This is because the electrons flow from the positive terminal on the battery to one plate, making this plate negative, but this then repels the electrons on the other plate away to the other terminal of the battery making this plate positively charged. In between the plates there is an insulating material (a dielectric) so that charge doesn't flow between them (as you seemed to think). The plates finally reach a dynamic equilibrium. There is subsequently a potential difference between the plates due to difference in charge as V=E/Q. I

It is necessary dor the plates to br close so that the electrons on the plates can repel each other.

I am not entirely sure why the are parallel, but I think it's again to do with the electrons repelling each other symmetrically so that it is equal but opposite charged plates.

Posted from TSR Mobile
Don't the electrons flow from the negative terminal to the capacitor plate, as electrons flow from the negative to positive terminals of the cell?

Also, what do you mean by a dynamic equilibrium - how does this occur?
6. (Original post by minnigayuen)
Don't the electrons flow from the negative terminal to the capacitor plate, as electrons flow from the negative to positive terminals of the cell?

Also, what do you mean by a dynamic equilibrium - how does this occur?
Sorry yes I will edit that, I got the positive and negative terminals mixed up.

The point about dynamic equilibrium is probably be invalid.

If you know care to explain as I am studying thid at a level too so I am no expert.

Thank you
7. (Original post by RATKING)
Sorry yes I will edit that, I got the positive and negative terminals mixed up.

The point about dynamic equilibrium is probably be invalid.

If you know care to explain as I am studying this at a level too so I am no expert.

Thank you
Oh i don't know either haha, i was hoping you would have some idea I knew it occurred in the production of Hall Voltage, but just wasn't aware it happened in a capacitor!

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