[Physics] Why is current the same in a series circuit

electric-circuitselectric-currentelectrical-resistance

So I am a 10th grade student and my teacher told me that the current is the same at every point in a series circuit. It does split up in parallel circuit but it then recombines and the current flowing out of the battery is the same as the current flowing back into it.

My question is – Why does the current remain the same?

I mean let's say that there is a light bulb somewhere in a series circuit. Now, current(or electrical energy) will flow into it and then convert into light energy.

But if the amount of current flowing into the filament of the bulb = the amount of current flowing out of the filament and at the same time it is producing photons(light energy) [and some heat energy too] then aren't we creating energy ? Which is not possible.

I am really confused and can't seem to grasp this idea. Please help.

Best Answer

I'm surprised that no one has yet mentioned the hydraulic analogy for electricity to help the OP understand better. A brief summary of this analogy is:

Electricity is like water flowing through pipes.
Current = amount of water flowing through pipe
Voltage = pressure of water
Power = water pressure x water flow (voltage x current)
Resistors = constrictions in pipe. Pressure (voltage) drops occur across them.

Any point in a (series circuit) pipe has the same amount of water flowing past that point as any other.

Any split in a pipe (parallel circuit) shares all water flowing into the split (the current of all legs equals the current before the split)

There are also water analogies for other electrical components like coils and capacitors; visit the link if you are interested.

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