# How a Toaster Works

By Pradeep Ankem

Topic: Machines

[Open the interactive Jig](https://ask.jig.com/j/L4zv2XxmxNcZ)

## Guide

### 1. Breakfast in a box

A toaster turns soft bread into crunchy toast in a couple of minutes\. There is no flame inside: just electricity, hot wires, a spring and a tiny magnet\. Drag the scene to look around\.

### 2. Look inside

Each slot is lined with heating elements: flat sheets of mica, a heat\-proof mineral, wrapped in thin nichrome wire\. Shiny wire guides keep the bread from touching them\.

Nichrome is a mix of about 80% nickel and 20% chromium\. It can glow red\-hot without burning away\.

### 3. Press the lever

The lever lowers a rack called the carriage, and the bread goes down with it\. Pushing it also stretches a spring that always wants to pull the bread back up\. Drag the lever down, or press the button\.

### 4. A magnet holds it down

At the bottom, the lever pushes two switch contacts together and electricity flows\. Some of it runs through an electromagnet: a coil of wire that is only a magnet while current flows\. It grabs a steel plate on the carriage and holds the bread down\.

### 5. Hot wires glow

Nichrome resists electricity, so the current makes it hot, glowing red at well over 500 °C\. The glowing wires send out invisible infrared light that toasts both sides of the bread at once\.

The bread's surface browns at around 150 °C, when sugars and proteins react\. This browning is called the Maillard reaction\.

### 6. The timer counts

A small circuit board counts the seconds\. The browning dial sets how long it waits: a longer wait means darker toast\. Slide to turn the dial and see the shade change\.

### 7. Pop\!

When time is up, the timer cuts power to the magnet and it lets go\. The stretched spring snaps the carriage up and the toast pops out\. Lifting the carriage opens the switch, so the wires cool down\.

The cancel button does the same thing early: it switches off the magnet\.

### 8. Electricity, a magnet and a spring

Hot wires make the toast, a magnet holds it down, a timer decides when, and a spring does the popping\. Next time you hear that pop, you'll know what just let go\.

Always unplug a toaster before reaching inside, and never poke it with a metal knife\.