Capacitor

[kingofjong]

Hi

I was wondering how much capacitance a capacitor would need to store 5 volt current. Basically I need to know what would C be for storing 1 bit.

Thanks

 

[BobK]

OMG! Where to start...

A capacitor does not store either voltage or current, it stores charge. The capacitance determines how much charge is stored for each volt. If you want to store current, look into inductors.

1 bit is not a measure of charge, current or voltage. It is a unit of information. 1 bit is the information of a binary choice, such as on / off or high / low or red / green. Any capacitor could be used to store 1 bit or more of information. It all depends on the interpretation of it. For instance, you might have a capacitor and charge it to 0, 1, 2 or 3 volts. This would be two bits of information.

Bob

 

[shrtrnd]

Can you tell us your application?

 

[Ratch]

Hi

I was wondering how much capacitance a capacitor would need to store 5 volt current. Basically I need to know what would C be for storing 1 bit.

Thanks

Current is measured in amps, not volts.

Ratch

 

[Ratch]

OMG! Where to start...

A capacitor does not store either voltage or current, it stores charge. The capacitance determines how much charge is stored for each volt. If you want to store current, look into inductors.

1 bit is not a measure of charge, current or voltage. It is a unit of information. 1 bit is the information of a binary choice, such as on / off or high / low or red / green. Any capacitor could be used to store 1 bit or more of information. It all depends on the interpretation of it. For instance, you might have a capacitor and charge it to 0, 1, 2 or 3 volts. This would be two bits of information.

Bob

Actually, a capacitor stores energy, not charge. The net charge on a capacitor energized to 100 volts is the same as it is on a capacitor not energized at all. The charge build up on one plate is counter balanced by the removal of the same amount charge on the opposite plate for a net charge change of zero. Since voltage is the energy density of the charge, (joules/coulomb), voltage is not stored in a capacitor because you cannot store density. Voltage is accumulated on a capacitor.

Coils also store energy, not current. The current in a coil is transitory, not stored.

Ratch

 

[davenn]

I have had to delete some threads as garbage physics and delete a couple of others that responded as a tidy up

the question has been asked and answered

A capacitor does not store either voltage or current, it stores charge.

Sorry Bob ... I have to agree with Ratch on this one .... a capacitor is energised, not charged
The net charge on a capacitor is zero regardless of if it has 0V or 100V across it

And that energy is stored in the electric field BETWEEN the plates


the thread is closed