How do thermometers work? I have already looked on Google and I cant find anything! Please help me!

Answer 1

Well, Thermometers work on the principle that the volume of a liquid increases as it is heated and decreases as it is cooled.
The bulb thermometer contains a fluid, usually mercury, which expands when it is heated.

Answer 2

Yes, the liquid expands when temperatures increase. Nowadays, though, mercury is not allowed to be used. Other substances which work like mercury are used.

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