Heat versus temperature

Answering the question, what's the difference between heat and temperature?

What’s the difference between heat and temperature?

Heat and temperature are often used interchangeably in conversation and they are related to each other, but they are different concepts. So let’s take a look at heat versus temperature and the difference between them.

What’s the difference between heat and temperature?

First, recall that all matter is made up of particles that are always in motion, whether they are rotating, vibrating, or moving.

What is heat?

Heat is a form of energy, and, like all forms of energy, it is able to do work. In this case, it is what makes the particles in a substance move.

It can also change the state of a substance, for example from a solid to a liquid. Heat is the total energy in a substance, in all the particles. The larger the substance, the more particles it contains, and therefore the greater the heat. Heat can’t be measured directly. Instead, the mass, temperature, and type of substance must be known.

What is temperature?

Temperature, on the other hand, is simply a measure of the average energy of the particles in a substance. It is not a form of energy, and cannot do work. It is measured with a thermometer in Kelvin, degrees Celsius, or degrees Fahrenheit.

Examples of heat versus temperature

Consider a bucket of water and a bathtub of water. A thermometer in each shows that they are at the same temperature. This means that the water molecules in each container are moving the same amount, on average. However, the bathtub of water contains far more heat because it contains far more molecules.

Now consider two pots, one of cold water and one of boiling water, and the same amount in each. Thermometers indicate they are at very different temperatures. The boiling water has the same number of molecules as the cold water, but each molecule is moving much faster, so the boiling water not only has a higher temperature, it also has more heat.

Finally, consider a pot of boiling water and a huge iceberg. The pot has a much higher temperature than the iceberg but because the iceberg is so massive, it actually has more heat than the pot of boiling water.

Heat will always transfer from hotter to colder objects. If two objects in contact with each other are the same temperature, heat will not be transferred between the two because the average energy of the particles (the temperature) is the same. However, if one object has a higher temperature, meaning its particles are moving faster on average, that energy will transfer to the colder object until they are both at the same temperature, or until the particles all have the same average energy.