When the handle lowers the bread, a wedge forces two contacts together which connects the power supply to nichrome wires wrapped around plates called mica sheets. Nichrome is a highly resistant material which converts electrical current into heat.
The spring-loaded tray forces a lever down which snaps into place under a metal tab, holding the bread inside. Sliding the release switch moves a magnetic element towards a metal sheet connected to the power supply.
Once they make contact the completed circuit activates the electromagnet, attracting the metal tab towards it. The lever is released, allowing the tray mechanism to spring back up. Out pops the toast!
Discover more amazing science in the latest copy of How It Works. It’s available from all good retailers, or you can order it online from the ImagineShop. If you have a tablet or smartphone, you can also download the digital version onto your iOS or Android device. To make sure you never miss an issue of How It Works magazine, make sure you subscribe today!