# A string of decorative lights is wired in series. A homeowner replaces the string with a new set wired in parallel. Describe two differences in how the current behaves in the parallel circuit compared with the series circuit.

> AQA GCSE Physics (8463) — 4.2.2 Series and parallel circuits · Describe · 4 marks

> A string of decorative lights contains six identical bulbs. In the original series circuit, when one bulb breaks the entire string goes out. The homeowner replaces it with a parallel circuit containing the same six bulbs.

## Mark scheme (4 marks)

1. In a series circuit the current is the same through every component / through the whole circuit; in a parallel circuit the current splits at each junction / branch
2. In the parallel circuit the total current from the source equals the sum of the currents through each branch
3. In the parallel circuit each bulb / branch has the same potential difference across it (equal to the supply potential difference), whereas in the series circuit the potential difference is shared between the bulbs
4. Because current can take more than one path in the parallel circuit, if one bulb breaks the others continue to work / the circuit remains complete for the other branches

## Key terms

- [series](https://www.gradenine.co.uk/glossary/series)
- [parallel](https://www.gradenine.co.uk/glossary/parallel)
- [current](https://www.gradenine.co.uk/glossary/current)

## Related

- [Revision notes for AQA GCSE Physics (8463)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-string-of-decorative-lights-is-92aff3ab) · Published by Druglandscape Ltd.