Electrical Circuit
Electricity and Magnetism

Adding bulbs in parallel: what happens?

Physics Narrative for 11-14 Supporting Physics Teaching

So what do you do and what happens?

Starting point: what happens when a second bulb is connected in parallel with the first?

When the circuit is completed, both bulbs light up, and each is of normal brightness (the same as with one battery and one bulb). When first encountered, this effect can seem a bit surprising, almost as if something is being gained for nothing.

Just by connecting the bulbs in parallel, they both shine with normal brightness. How can we explain this observation using the electric circuit model?

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