You wake up in a haze in the morning and drowsily walk down the stairs take out some whole wheat bread and pop it into the toaster to be pleased by the sight of evenly browned toast in 45 to 90 seconds. What you didn't realize was physics was the reason your toast was made so well!
It may sound silly but any normal toaster uses physics to make your morning snack. A toaster usually is made up of a simple circuit constituting of a power source, the plug in the wall, a giant resistor and a simple timer to make sure your bread isn't burnt! The resistor in your toaster is made up of an alloy because it provides a high resistance, the most commonly used is Nichrome, or Nickel combined with chromium. The Nichrome is wound in tight coils to increase its length and therefore resistance so that when a current is run through it the coils give off extreme heat which warms up your toast for you to consume with your favorite jam, jelly or simple butter.
The idea is quite simple as we know the resistance of a length of wire is equal to the resistivity for metal (very high for chromium) times the length of the wire, which is made longer by coiling, divided by the cross sectional area, which is usually very thick for the chromium coils to create maximum heat.
So next time you make your toast remember to thank your local physicist, you'd just be eating cold bread without them!
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