Electrical Circuit
Electricity and Magnetism

## Build and model electrical loops - Physics narrative

Physics Narrative for 5-11

A Physics Narrative presents a storyline, showing a coherent path through a topic. The storyline developed here provides a series of coherent and rigorous explanations, while also providing insights into the teaching and learning challenges. It is aimed at teachers but at a level that could be used with students.

It is constructed from various kinds of nuggets: an introduction to the topic; sequenced expositions (comprehensive descriptions and explanations of an idea within this topic); and, sometimes optional extensions (those providing more information, and those taking you more deeply into the subject).

### An introduction

Electrical Circuit
Electricity and Magnetism

## What happens in circuits? (5-11)

Physics Narrative for 5-11

## Describing circuits

When a battery is connected to a bulb to make a complete circuit, the bulb lights up. If you are interested in understanding how electric circuits work, this familiar event raises a number of questions.

While the bulb is lit the battery is flattened and the filament of the bulb glows and light is emitted (see the SPT: Energy topic and the SPT: Electric circuits topic for more detail).

The bulb lights up very quickly as the circuit is completed. The situation flips from one steady state, where there is very little happening, to a steady state, where the bulb is glowing, very quickly. We're going to suggest that you concentrate on the steady state, where the bulb is glowing steadily.

What's needed is a way of thinking about electric circuits that allows you to reason about what's going on inside them (inside the battery, wires and bulb). You can see the effect of what's going on (the bulb lighting up); what is needed is a model for the electric circuit to support you as you help children who want to explore this process.

Most of this Physics Narrative is for your benefit, and there is just too much here for primary-age children.