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# Capacitors watch

1. Please could someone explain the following questions:

When a capacitor discharges, why doesn't the current go round and attract to the other plate, charging the capacitor again?

When a capacitor has fully discharged, what does the charge configuration look like? Is there just extremely little negative charge on the plates at this point?

Does the Q in the capacitor discharge equation relate to the amount of negative charge on the plates, or both the negative and the positive?

Sorry if these questions are factually incorrect, but help would be much appreciated!
2. (Original post by PhyM23)
Please could someone explain the following questions:

When a capacitor discharges, why doesn't the current go round and attract to the other plate, charging the capacitor again?

When a capacitor has fully discharged, what does the charge configuration look like? Is there just extremely little negative charge on the plates at this point?

Does the Q in the capacitor discharge equation relate to the amount of negative charge on the plates, or both the negative and the positive?

Sorry if these questions are factually incorrect, but help would be much appreciated!
No. The current actually decreases the charge on the other side. Picture electrons moving off of the negative plate, around the circuit and onto the positive plate, decreasing the charge on the positive plate.

When it's fully discharged both plates are neutral. If it's charged and left to discharge then, using a continuous approximation, it won't actually be fully discharged in a finite amount of time so the language can be bent slightly to consider a very small charge as roughly discharged.

The magnitude of the charge on one of the plates. Either the positive or negative plate. It can also be considered as the charge that has moved from one plate to the other, with both plates starting as neutral.
3. (Original post by morgan8002)
No. The current actually decreases the charge on the other side. Picture electrons moving off of the negative plate, around the circuit and onto the positive plate, decreasing the charge on the positive plate.

When it's fully discharged both plates are neutral. If it's charged and left to discharge then, using a continuous approximation, it won't actually be fully discharged in a finite amount of time so the language can be bent slightly to consider a very small charge as roughly discharged.

The magnitude of the charge on one of the plates. Either the positive or negative plate. It can also be considered as the charge that has moved from one plate to the other, with both plates starting as neutral.
This is just what I was looking for. Thank you very much

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