The most common electrical items in our home nowadays are toaster. Toaster is a small electrical kitchen appliance which designed to toast slices of bread, an act also known as 'making toast'. A typical modern 2-slice toaster draws anywhere between 600 and 1200 W and makes toast in 1 to 3 minutes.
Modern toasters are typically one of three varieties: pop-up toasters, toaster ovens and conveyor toasters. In pop-up or automatic toasters, bread slices are inserted vertically into slots (generally only large enough to admit a single slice of bread) on the top of the toaster. A lever on the side of the toaster is depressed, activating the toaster. When an internal device determines that the toasting cycle is complete, the toaster turns off and the toast pops up out of the slots. The heating elements of a pop-up toaster are usually oriented vertically, parallel to the bread slice - although there are some variations.
Sometimes toast gets stuck in a toaster, particularly pop-up toasters, and must be freed manually. As most toasters are in the kitchen, metal knives and forks are typically an easily available tool but are inadvisable to use, due to the risk of electric shock, unless the appliance is disconnected from the mains.
The basic idea behind any toaster is simple. A toaster uses infrared radiation to heat a piece of bread (see How Thermoses Work for information on infrared radiation). When you put your bread in and see the coils glow red, the coils are producing infrared radiation. The radiation gently dries and chars the surface of the bread.
The most common way for a toaster to create the infrared radiation is to use nichrome wire wrapped back and forth across a mica sheet, Nichrome wire is an alloy of nickel and chromium. It has two features that make it a good producer of heat. The very simplest toaster would have two mica sheets wrapped in nichrome wire, and they would be spaced to form a slot about an inch (2.5 cm) wide. The nichrome wires would...