How Thermometers Work

man with thermometer in bed
Too much stress making you sick? Using a thermometer will help tell. See more stress pictures.
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­If you look around your house, you will find lots of different devices whose goal in life is to either detect or measure changes in temperature:

  • The thermometer in the backyard tells you how hot or cold it is outside.
  • The meat and candy thermometers in the ­kitchen measure food temperatures.
  • The thermometer in the furnace tells it when to turn on and off.
  • The thermometer in the oven lets it keep a set temperature (hot).
  • The thermometer in the refrigerator lets it keep a set temperature (cold).
  • The fever thermometer in the medicine cabinet measures temperature accurately over a very small range.

­In this article, we will look at the different thermometer technologies used today and understand how they work. You wil­l also get to build your own thermometer!­