Why dc can be stored ac cannot stored?
Why direct current (DC) can be stored but alternating
current(AC) can not be?
Current means flow of charge per unit second.
Any flow cannot be made stationary. Then it is not flow.
Hence both direct current and alternating current cannot be
stored.
We can store only charges.
In capacitors we store charges and not current.
For storing we use direct supply or direct voltage
When a capacitor is connected to a battery, which is a source of
direct voltage, each plate of the condenser get charged. Charges
remain in the plates. No current flows in between the plates.
When the source is removed, there are some charges left in the
plates.
We say that charges are stored in the plates.
If an alternating source of supply is connected in between the
plates,every instant ,the charges in the plates are alternating and
they are not stationary.
When ac supply is removed, all the charges move out of the
plates and hence no charge is left in them.
Hence charges can be stored with dc supply and not with ac
supply.
However as long as the ac is connected to the capacitor, the
capacitor gets stored and emptied with the frequency of the ac
supply.