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Assume We have a simple electrical circuit with a DC Source of constant emf. And I am talking about the ideal case. The circuit also consists of "Push-Key" or a normal switch whatever you like.

The circuit has wires of negligible resistance.

Initially the battery is not inserted in the circuit.

At t=0 , We insert the battery with the switch open

According to me what happens is......

The battery's positive terminal attracts the electrons from the wire that are connected to it externally. Now the electrons that are at the positive terminal are pushed towards the negative terminal against the Lorentz force (That is what a battery does right?) edit : inside the battery

And then The electrons are released by the negative terminal of the battery in the wire connected to it externally.

As the switch is not closed, there should be no electric field (circuit is not complete so the wire acts like a conductor would) inside the wires and these charges therefore accumulate on the surface of the wire.

This process Happens very fast and up until the switch.

One side of the switch has negative surface charges, and the other positive surface charges..

Also the surface charges that are being set up start creating their own repulsive forces for the incoming electrons...Reducing further flow until the switch ( They wont flow across the switch as the circuit is not complete) This thing also explains the leakage current for me. Some surface electrons somehow jump the gap.

The setup process stops when the potential of the wires becomes equal to the terminals it is connected to (In the ideal case.. Wires with negligible resistance)

In the image switch is denoted by the open circuit.

Also, I read somewhere that even small disturbances in the electron sea can set up the surface charges.

So this process is really quick and does not require much energy.. Hence no energy loss of battery or something like that

And this is how surface charges are set up....

Now, At t= T , we close the switch... The surface charges on either side (near the switch not everywhere in the circuit) neutralize each other causing a net field inside the wire and current starts flowing. (I read this thing somewhere)

So, is there anything I understand wrong about surface charge setup? Battery is the active element in the circuit and so it makes sense that its terminals should affect the wire electrons is some way(Even if circuit is incomplete).

I found this on google

The Image is just the representation of what I am saying. Focus on the surface charges and not anything else.

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Mostly correct.

Now the electrons that are at the positive terminal are pushed towards the negative terminal against the Lorentz force

No, along the Lorentz force, and due to the Lorentz force. (OP later clarified that the intention of this part is to discuss the insides of a battery, in which case, yes, it goes against the Lorentz force.)

As the switch is not closed, there should be no electric field (circuit is not complete so the wire acts like a conductor would) inside the wires and these charges therefore accumulate on the surface of the wire.

No, for the fast transient period, there will be electric field and current flow on the inside of the conductors too. It is just that these transients quickly decay away, leading to the equilibrium conditions as you expect.

So this process is really quick and does not require much energy.. Hence no energy loss of battery or something like that

It is quick, but it may use energy. It is just not continuously using energy for a long long time. We are not very sensitive to continuous but only a sudden bit of using energy.

Now, At t= T , we close the switch... The surface charges on either side (near the switch not everywhere in the circuit) neutralize each other causing a net field inside the wire and current starts flowing. (I read this thing somewhere)

Not completely neutralised. You still need a bit of them to setup the electric field inside the conductor so that the current will keep flowing.

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  • $\begingroup$ The lorentz force would try to keep the electrons at the positive terminal right?? So against? The electric + magnetic force = lorentz $\endgroup$
    – The Interpreter
    Commented Sep 13 at 12:04
  • $\begingroup$ The electrons are pushed against the Lorentz force law by chemical processes inside the battery. Outside the battery, they are pushed by Lorentz force law. The positive terminal of a battery sucks in electrons from the wire connected to it. $\endgroup$
    – naturallyInconsistent
    Commented Sep 13 at 12:11
  • $\begingroup$ And So inside the battery its against the lorentz force and that is what I meant and Thanks for the help . I appreciate it $\endgroup$
    – The Interpreter
    Commented Sep 13 at 12:13
  • $\begingroup$ You should not edit my answer when you edited your own question. That is rather rude. Let answerers do the editing themselves. $\endgroup$
    – naturallyInconsistent
    Commented Sep 13 at 12:27
  • $\begingroup$ I am sorry I just tried to correct it so others reading it wont get confused. Really Sorry. I hope you would forgive me for that $\endgroup$
    – The Interpreter
    Commented Sep 13 at 12:28

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