What is temperature?

What is temperature? In order to define temperature, we use a quantity. This quantity will then tell us how hot or cold something is compared with a standard temperature. 

Now you may wonder what we mean by standard temperature.

The standard temperature is the temperature at which water freezes.

After careful experimentations and observations, Celsius defined this temperature to be 0 and we write 0°C

Once we have 0 degree, which is the freezing point of water, as our standard , any temperature that is colder or warmer can be measured relatively to 0 degree.

While 0 degree is the freezing point of water, 100 degrees is the boiling point of water.

Celsius is not the only scale that we use to measure temperature.

Another commonly used scale specially in the United States is the Fahrenheit.

0 degree in the Celsius scale corresponds to 32 degrees in the Fahrenheit scale

0°C = 32°F

This means that the freezing point of water in the Fahrenheit scale is 32 degrees. We show you below an example of a thermometer with some celsius and Fahrenheit temperature. 

Right now this thermometer reads 50 degrees Celsius or 122 degrees Fahrenheit. 

What is temperature in relationship to kinetic energy?

We can also define temperature in terms of its kinetic energy. Recall kinetic energy refers to energy in action or something that is moving.

Recall also that we explained all matter is composed of atoms moving about lightly and quickly.       

       Therefore, the atoms in matter have kinetic energy

This kinetic energy  in atom or molecules is what causes something to become warm.

The warner something is,  the higher the kinetic energy generated by the atoms of that thing. 

Recall also that the kinetic energy depends on the mass and the speed. 

Since the mass of an atom is not likely to change, the magnitude of the kinetic energy will depend mostly on the speed. 

This means that the warmer the object gets, the faster the movement of the atoms or molecules of that object.

One more temperature scale

The Kelvin scale is used mostly in scientific experiment. In this scale, the number 0 is assigned to the lowest possible temperature.

Notice that it is not feasible to reach this lowest temperature in real life

If we could, it would correspond to -273.15 °C or -459.67 °F

For such lowest temperature, atoms or molecules in objects will not move and have no kinetic energy.

Recent lesson

  1. Law of Reflection

    Mar 16, 17 03:15 PM

    Great lesson about the law of reflection. Crystal clear explanation

    Read More

Enter Your E-mail Address
Enter Your First Name (optional)
Then

Don't worry — your e-mail address is totally secure.
I promise to use it only to send you Physics lessons.

New! Comments

Do you like the physics lessons on this site? Have your say about what you just read! Leave me a comment in the box below. Please share the lessons with your friends as well!