A Detailed Synopsis on Temperature and Temperature Scales

Temperature Scales

Any substance’ temperature is basically the degree of its heat or coldness of that particular substance. Hot matter is said to have high temperature, while cold matter has low temperature. So, any substance’ temperature is actually the indication of the average kinetic energy of the molecules of that particular matter. It is a well-known fact that hotness always flows from a body having a higher temperature to some other body which is at a lower temperature than that one. So, this can also be explained in a way that body temperature is basically the property, which is controlling the heat flow. This can be easily shown as this. When any 2 objects having the same type of material are put together, the higher temperature one cools, while the cooler object heats up, until a point is reached at which no further change occurs. 

Heat Balance 

Thermal energy flows from an object with a higher temperature to another at a much lower temperature. In other words, heat flows from a warmer body to a colder one. Heat energy continues to flow from the hotter to the cooler body until the temperatures of both of those bodies come at the same degrees. At that point those 2 bodies are said to reach thermal equilibrium. When 2 bodies reach the same temperature, they are called to be in thermal equilibrium with one other, because only then, heat is not transferred from one body to the other one. The temperature therefore reached is known as the equilibrium temperature. So, we can now say that temperature is actually a quantity that is the same for both systems when they reach the state of thermal equilibrium. 

The Zeroth Law of Thermodynamics 

This Law defines about the 2 systems stating that if they are individually in the state of a thermal equilibrium with the third ones, they should also be in the similar state with one other, and they’ll have the similar temperature, irrespective of which system they actually are.” This law can be reformulated as: If there are 3 or more systems that together are in thermal contact and also in a state of thermal equilibrium, then any 2 systems that are taken together come in equilibrium with one other. 

Temperature Scale 

One of the first attempts to create a standard temperature scale happened in the past when Galen proposed in his medical writings a “neutral” standard temperature consisting of equal amounts of boiling water and ice; on both sides of this temperature there were 4 degrees of heat & 4 degrees of cold, respectively. The oldest temperature gauge or device was called a thermoscope.