2006-09-19 23:28:30 · 11 answers · asked by unao12345 1 in Science & Mathematics ➔ Other - Science
It is a liquid metal "mercury" which is highly sensitive to heat and it expands with temperature. the higher the temperature the more it expands.
2006-09-19 23:30:50 · answer #1 · answered by rinah 6 · 0⤊ 0⤋
Here's what energyquest.ca.gov says about thermometers:
How A Thermometer Works
When you look at a regular outside bulb thermometer, you'll see a thin red or silver line that grows longer when it is hotter. The line goes down in cold weather.
This liquid is sometimes colored alcohol but can also be a metallic liquid called mercury. Both mercury and alcohol grow bigger when heated and smaller when cooled. Inside the glass tube of a thermometer, the liquid has no place to go but up when the temperature is hot and down when the temperature is cold.
Numbers are placed alongside the glass tube that mark the temperature when the line is at that point.
The other type of common thermometer is a "spring" thermometer. A coiled piece of metal that is sensitive to heat is used. One end of the spring is attached to the pointer. As the air heats, the metal expands and the pointer moves higher. As the air cools, the metal contracts and the pointer moves lower. Typically, these type of thermometers are less accurate than bulb or digital thermometers.
2006-09-20 06:46:27 · answer #2 · answered by LadyLgl 3 · 0⤊ 0⤋
Almost everything expands when heated and contracts when cooled even glass and mercury or red-dyed alcohol. If you trap a quantity of liquid within a glass thermometer (with a relatively large bulb and a long narrow hollow path) the liquid will expand (mostly in the bulb) more than the glass when heated driving the excess liquid up the hollow tube. You can mark (graduate) the tube at two or more known temperatures, and add a scale (in degrees C or F) and use it to estimate all temperatures on the scale within the accuracy of the scale.
2006-09-20 08:01:40 · answer #3 · answered by Kes 7 · 0⤊ 0⤋
Liquids in the thermometer expands according to heat. It is a simple principle that molecules of matter expand upon heating and contract upon cooling.
2006-09-20 07:11:57 · answer #4 · answered by Hardrock 6 · 0⤊ 0⤋
Hey there.
I believe its to do with the liquid inside, which is usually mercury, which takes up less or more space depending on how hot or cold it is due to the liquid expanding.
2006-09-20 06:33:50 · answer #5 · answered by June 2 · 0⤊ 0⤋
I think it's something to do with the liquid expanding under heat and contracting when cold
2006-09-20 06:30:45 · answer #6 · answered by Anonymous · 0⤊ 0⤋
Liquids expand when they are warm, and contract as they cool.
When water freezes, it expands. That is why we do not use water in glass thermometers.
Next time, pay attention in class. Then we will not have to do your homework for you.
2006-09-20 06:37:55 · answer #7 · answered by GreenHornet 5 · 0⤊ 0⤋
It's called Mercury
2006-09-20 06:32:22 · answer #8 · answered by Anonymous · 0⤊ 0⤋
the volume of the liquid changes with changes of it's temperature, the design of the thermometer magnifies these minute changes
2006-09-20 06:31:51 · answer #9 · answered by Anonymous · 0⤊ 0⤋
its mercury and I think one of its properties is to expand and contract on temperature change
2006-09-20 06:35:48 · answer #10 · answered by noogney 4 · 0⤊ 0⤋