Temperature - Middle School 1st grade - 2nd semester

한글

There is a glass of water. A girl says it's hot, but her friend says it's warm. Why does it feel different, even though it's a same glass of water? And how should we show how it feels? 'Temperature' is made because of that, and I will tell more about it.

Temperature, in the dictionary means 'numerical measure of hot and cold.' Could a person just grab something and say 'Hmm, this thing is 30 degrees Celsius'? Of course not. We can't tell the temperature by our own.

Then let's talk about what kind of temperature are there in the world.

The main temperature in the world are Celsius, Fahrenheit, and Kelvin. Commonly, in many countries, the temperature when water becomes frozen, the temperature is zero, and when it boils, the temperature is one hundred. Like this, dividing into 100 parts, putting the freezing point of water, and the boiling point of water in standard.

Also, there is another measure, used a lot in countries like America. It's called 'Fahrenheit'. Water freeze when temperature is 32℉ and boils when it is 212℉ We divide Fahrenheit into 180 parts.

Lastly, the temperature is Kelvin. If you want to learn about Kelvin, you will have to know about 'Absolute zero'. So, what is this 'Absolute zero'?

Absolute zero is the lowest temperature in thermodynamic, and is 273 below zero in Celsius. Absolute zero was asserted by a scientist called 'Kelvin', and it got hints from 'Charles's rules'. Charles's rule says the gas's volume get 1/273 bigger as the temperature gets 1℃ higher. If the volume gets 1/273 lower every time the temperature goes 1℃ lower, if the temperature is 273 Celsius below zero, the volume will be zero. In other worlds, the volume decreased as much as it can and cannot decrease more. So that means there can be no lower temperature than 273 Celsius below zero. This is 'Absolute zero'. Meanwhile, 'Kelvin' is a unit of measure, putting basics in absolute zero. And when we compare Celsius and Kelvin, just and 273 to Celsius. I will show you the example.

Also, remember that since volume increase 1/273 per 1℃, if the temperature is 273℃, the volume gets twice as big as the original one.