How Does Current Initially Flow in a Circuit with a Capacitor?

[sunilmaurya]

Hey...i got a confusion @ how a circuit allows the current to flow initially when voltage source is applied across the capacitor.??
U know as per the concept the current flow in the circuit only if the circuit completes...? isn't it like that the dielectric between the plates of the capacitor will not allow the electron to flow through it...??
so how the electrons will get the complete path to flow...?

Plz answer it...pleasezzz.

 

[n.karthick]

As you mentioned the current does not flow inside the dielectric of capacitor. Only the charges (of opposite sign) move outwards from capacitor plates to the voltage source which gives the illusion that circuit is completed.

 

[cragar]

The electric field from the battery cause electrons to build up on one of the plates . And as charge builds up on one of the plates this E field pushes charge away from the other plate . This all happens at once . So its the E field that does it .

 

[Pranav Jha]

exactly the confusion i had to struggle with when i started studying about capacitors (2 months back). No teacher seems to care about answering this question. However, i hope this page clears your confusion my friend!
I think that when we bring two ends of a copper wire together with an infinitesimal distance separating them, the two ends can act as the plates of a capacitor!
http://amasci.com/emotor/cap1.html

 

[sardar]

Hello there,

I can understand your confusion about how a circuit allows current to flow initially when a voltage source is applied across a capacitor. Let's break down the basic concepts to help clear things up.

Firstly, a capacitor is a passive electronic component that is designed to store electrical energy in an electric field between two conductive plates. When a voltage source is applied across a capacitor, the plates become charged, with one plate having a positive charge and the other having a negative charge.

Now, to address your question about the flow of current. In a circuit, current flows from the negative terminal of a voltage source to the positive terminal. This flow of current is driven by the difference in potential between the two terminals. In the case of a capacitor, the potential difference between the charged plates creates an electric field.

When a voltage source is applied across a capacitor, the electric field between the plates is initially unbalanced. This creates a flow of current as the electrons move from one plate to the other, trying to balance out the electric field. However, as the electrons move, they create an opposite electric field that opposes the initial field, eventually stopping the flow of current.

Therefore, in a circuit with a capacitor, the current initially flows as the electric field between the plates is being established. Once the field is balanced, the current stops flowing. This is known as charging a capacitor.

I hope this explanation helps to clarify things for you. If you have any further questions, please do not hesitate to ask. Keep exploring and learning about basic concepts in electronics!