Examples and Applications of Zeroth Law of Thermodynamics

The zeroth law of thermodynamics can be used to compare the temperatures of multiple objects in physics. If heat can move between two items, but no heat is passing between them, they are in thermal equilibrium. If the temperature of the swimming pool you are in is the same as yours, no heat is transferred from you to it or from it to you (although the possibility is there). You have reached a state of thermal equilibrium.

In contrast, if you leap into a pool in the winter and break through the ice, you will not be in thermal equilibrium with the water. You don’t want to be in that situation. (This physics experiment is not to be attempted at home!)

You should use a thermometer to check for thermal equilibrium (particularly if you’re about to leap into a frozen swimming pool). You can use the thermometer to check the pool temperature before checking your own. You’re in thermal equilibrium with the pool if the two temperatures concur. 

Before coming to the Zeroth Law of Thermodynamics example and applications, let’s discuss its definition.

What is Zeroth of Thermodynamics?

According to the Zeroth Law of Thermodynamics, if two bodies are present and each is in thermal equilibrium with a large object, they all seem to be in equilibrium with one another. Because the other two laws of thermodynamics were observed and recognised before this law, it was given this name. However, it was discovered that this law was more fundamental than the other two laws. Thus, it was given the moniker Zeroth Law of Thermodynamics.

Origin of the Zeroth Law

The field of research known today as thermodynamics was founded at the turn of the nineteenth century. At the time, very little was known about the atomic and molecular characteristics of matter. As a result, scientists had to rely on macro-level data.

Work, pressure, temperature, and energy transformations were the most common. The first, second, and third laws of thermodynamics were developed as a result of these observations. One of the consequences of these principles was the assertion that the development of an ideal machine was impossible – a popular theory that involved creating a machine that, after receiving a certain amount of energy to start, would run perpetually without requiring additional energy.

Now we’ll use some examples to try to grasp the zeroth law of thermodynamics.

Assume that there are three bodies: A, B, and C. It’s in a state of thermal balance. Assume that body A has temperature T1, body B has temperature T2, and body C has temperature T3. As we all know, there must be a temperature differential for heat transmission to occur. As a result, we include temperature differences in the work of the zeroth law. As a result, T1>T2>T3

As a result, temperature T1 exceeds temperature T2. T2 is higher than T3, while T3 is lower. As a result, the temperature will transfer from T1 to T2 and finally to T3. After some time has passed, we’ve discovered that all of the bodies A, B, and C have ceased to transfer heat.

Zeroth Law of Thermodynamics: Application

If you want to reliably measure temperature, you’ll need a reference body and a temperature-dependent feature on that body. The shift in that feature could be taken as a shift in temperature. This characteristic is referred to as a thermodynamic property.

The most common application of the Zeroth Law of Thermodynamics is the thermometer. Using a simple thermometer containing mercury in a tube, we may watch the Zeroth law in operation. The mercury expands as the temperature rises because the tube’s area remains constant. The height has risen as a result of this development. Temperature differences are now visible in the variation in the height of the mercury label, which helps us measure it.

Using two glasses of water, another demonstration of the zeroth law of thermodynamics can be seen. The hot water will be poured into one glass, while the cold water will be poured into the other. They will eventually establish thermal equilibrium with the temperature of the room.

Why is it called Zeroth?

What is the origin of the term “zeroth law of thermodynamics”?

Answer: Originally, three thermodynamic laws were formulated and titled. Because the law is so basic, the scientist Ralph H Fowler devised an alternative, assigning a lower number zero to the new law, which he dubbed the “Zeroth law.”

Conclusion

That’s a wrap to the Zeroth Law of Thermodynamics example and applications. The temperature is dealt with by the zeroth law of thermodynamics. That is, the transfer of heat from one thermal equilibrium body to another is represented by the zeroth law of thermodynamics.