We can feel heat and cold but we can’t really see it. What is actually happening and why do we prefer a specific temperature?
In: Physics
Heat is energy in the form of molecules moving around in sort of random chaotic vibrations. This is easiest to imagine for a gas, where the molecules travel long distances in straight lines between collisions. It is (for reasons based in statistics) the ‘final form’ of all mechanical energy. A moving object will tend to convert its motion energy into heat.
For those same statistical reasons, heat spreads out evenly. If you have heavy molecules and light molecules, the light molecules will tend to move faster in order to have the same energy (on average) as the heavier ones. The electrons and atoms and such all get their split of the heat energy.
Heat indirectly results in temperature. Adding heat to an object usually raises its temperature, although some processes (such as melting or boiling) absorb heat without raising the temperature.
Many chemical processes, like the aforementioned melting and boiling, act differently with different amounts of molecular motion. That’s what melting is, really; a material acting differently because its molecules have more energy.
Humans have many chemical processes in our bodies. These processes happen at different speeds and in different ways – especially in the deeper core of our bodies it is critical that each of these processes operate consistently in the same way. To allow this, we maintain a specific internal temperature. To help maintain an internal temperature, our bodies change many things, but that’s its own eli5.
Latest Answers