# Explain what happens to the current and voltage in a series circuit when an extra resistor is added to the circuit.

> WJEC GCSE Physics (Wales) — 1.1 Electric circuits · Explain · 4 marks

> A student has a series circuit containing a battery, a bulb, and a switch. The student adds an extra resistor in series with the bulb.

## Mark scheme (4 marks)

1. The total resistance in the circuit increases
2. The current in the circuit decreases
3. The voltage of the battery/supply is shared between more components
4. The voltage across the bulb decreases (because it shares the supply voltage with the added resistor)

## Key terms

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

## Related

- [Revision notes for WJEC GCSE Physics (Wales)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" 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/explain-what-happens-to-the-current-d29e4fc1) · Published by Druglandscape Ltd.