Zeroth Law of Thermodynamics Definition, History and Examples

What Is Zeroth Law Of Thermodynamics?

The Zeroth Law Of Thermodynamics is one of the most important physical laws of thermodynamics which states that if two thermodynamic systems are in thermal equilibrium with the third thermodynamic system, then they all are in thermal equilibrium with each other.

Must read, Top 6 Applications Of Charles Law

In other words, if system A is in thermal equilibrium with system B. On the other hand, system B is in thermal equilibrium with system C. Then according to Zeroth law of thermodynamics definition, system A is Bound to be in thermal equilibrium with system C.

What Is Thermal Equilibrium?

According to the thermal equilibrium definition, when two thermodynamic systems or simply speaking two thermal bodies are in thermal contact with one another, separated by a barrier (permeable only to heat). Then, there will be no transfer of heat energy between two physical systems.

thermal-equilibrium-due-to-zeroth-law-of-thermodynamics
Thermal equilibrium is reached and net heat transfer is equal to zero/Credit: Wikimedia Commons

Don’t get confused (see the above image). I mean, practically there will be a transfer of heat from one system to another. But, the net transfer of heat will be equal to zero.

 

History Of Zeroth Law Of Thermodynamics

Years before the discovery of the Zeroth Law, the whole scientific community was well aware of the other Laws of thermodynamics. The 3 laws of thermodynamics are – First Law of thermodynamics, Second Law, and, Third Law Of Thermodynamics.

Why Is The Zeroth Law Of Thermodynamics Important?

As I said, the whole scientific community was well aware of the theory of thermodynamics. But none of the available theory was able to accurately define the temperature. Therefore, when Zeroth Law was discovered, it superseded all the other laws of thermodynamics to accurately define the temperature.

Recommended, Top 6 Naming Of Chemical Elements After Famous Scientists

For this reason, the definition of temperature given by the Zeroth law is regarded as the empirical definition of temperature.

Not to mention, the old laws of thermodynamics were even given their respected nomenclature (like 1st, 2nd, 3rd). With this in mind, the whole scientific community was puzzled by the fact that the newly discovered law is far more superior than the original 3 laws of thermodynamics.

In that case, zeroth law should be named above all in the existing literature. But it would have created a mess. Simply because the other 3 laws of thermodynamics were well known by their assigned nomenclature. Therefore, renumbering them would obviously create a conflict among the whole scientific world.

image-of-ralph-fowler
Credit: The Academic Family Tree

Finally, in the year 1935,  this mess was ended by the British physicist and astronomer Ralph H. Fowler who formulated the name known as Zeroth Law.

 

Zeroth Law Of Thermodynamics Examples

Well, in my view, in order to find something; we don’t need to think deeply. All we need to do is think clearly. The same goes for Examples Of Zeroth Law Of Thermodynamics.

I mean, there is so many zeroth law of thermodynamics examples that can be seen in our everyday life. And the most common example is Thermometer.

Working Of Thermometer

zeroth-law-example
Sickman checking his temperature using a thermometer/Credit: Clker

I hope you are well aware of the fact that what is a thermometer? And how a thermometer works? But the thing you don’t know about thermometer is its working principle. The working of the thermometer is solely based on the zeroth law.

A thermometer is the perfect example of the Zeroth Law Of Thermodynamics. If you don’t believe me check yourself. Just put a neutral thermometer under your tongue for say one minute. You will see that whatever is your body temperature, it will be shown on the thermometer.

Highly Recommended, Top 6 Real-Life Gay Lussac Law Examples

The other day to day example will be – like take a glass of normal water (say at 27-degree Celsius) and boiling water (say at 100-degree Celsius) and put them in your freeze for 4 or 5 hours.

Later you will see that the normal water and the boiling water have reached thermal equilibrium with respect to the temperature of the freeze.

That’s it for this post. If you like this article, share it if you like it, like it if you share it. You can also find us on Mix, Twitter, Pinterest, and Facebook.

You might also like:

I am a mechanical engineer by profession. Just because of my love for fundamental physics, I switched my carrier, and therefore I just completed my postgraduate degree in physics. Right now I am a loner (as like ever) and a Physics blogger too. My sole future goal is to do a Ph.D. in theoretical physics, especially in the field of cosmology. Because in my view, every part of physics comes within the range of cosmology. And I love traveling, especially the Sole one.

Leave a Comment