Absolute Zero: Definition, Formula & Importance

An Absolute zero is the temperature at which particles constitute a minimal amount of heat. An absolute zero is also called the zero kelvin because it is zero on the Kelvin scale. The value of the Absolute Zero in Fahrenheit is 459.76 degrees Fahrenheit, and the value of Absolute Zero in Celsius is -273.15 degrees Celsius. We call this the lowest temperature a thermodynamic system bears. However, the concept of Absolute 0 remains a theoretical concept.

In this article, we will learn about Absolute Zero Temperature in detail. 

Zero Kelvin

We say that an Absolute zero is the lowest value on the thermodynamic temperature scale. 

We can say that absolute zero temp is a state at which the enthalpy-and-entropy'>enthalpy and entropy of a cooled ideal gas reach their minimum value, taken as zero kelvin. The basic particles of nature have the lowest vibrational motion, containing only quantum mechanical and zero-point energy-induced particle motion.

It is the point at which the Kelvin and Rankine temperature scale set their zero points at absolute 0. 

Absolute Zero Temperature

According to the Classic Kinetic Theory, absolute zero represents the absence of movement of individual molecules in a substance whereas the experimental evidence shows this isn't the case, rather, it indicates that particles at absolute zero have the lowest vibratory motion. 

In simple terms, heat may not be removed from a system at absolute zero, there might be some heat stored in it, so it clearly states absolute zero does not represent the lowest possible enthalpy state.

In the field of quantum mechanics, absolute zero represents the lowest internal energy of solid matter in its zero/ground state.

Absolute Zero and Temperature

In Physics, we describe the hotness or coldness of an object with the term ‘temperature’. The temperature of an object depends on the velocity at which atoms and molecules inside it oscillate. Though absolute zero represents oscillations of atoms at the slowest speed; however, their motion never completely stops.

So, do you think is it possible to reach absolute zero, or we can have an absolute zero in Fahrenheit and an absolute zero in Kelvin?

No, it is not possible to get an absolute zero in Fahrenheit and an absolute zero in Kelvin. However, scientists made it possible. Now, let’s understand how.

From the above text, we learned that reaching absolute zero is not possible, though scientists have approached this level. Some of the record-breaking examples are as follows: 

Did you Know?

In 1994, NIST aka The National Institute of Standards and Technology achieved a record cold temperature of 700 nK, i.e., billions of kelvin. 

In 2003, MIT aka Massachusetts Institute of Technology researchers set a new record of 0.45 nK.

Absolute Zero

Absolute Zero Temp can be thought of as the lowest temperature possible; however, it is not the lowest enthalpy state possible because all real substances begin to depart from the ideal gas behavior on being cooled as they approach the change of state to liquid, and then to solid; and the sum of the enthalpy of vaporization viz: gas to liquid state and enthalpy of fusion, i.e., change from a liquid to solid state exceeds the ideal gas's change in enthalpy to absolute zero. 

In the theory of quantum mechanics, matter (solid) at absolute zero is in its ground state, i.e., the point of lowest internal energy.

Absolute Zero Temperature

As per the laws of thermodynamics, absolute zero cannot be reached using only thermodynamic means, it’s because the temperature of the substance being cooled approaches the temperature of the cooling agent asymptotically. Also, the system at absolute zero still bears quantum mechanical zero-point energy, i.e, the energy of its ground state at absolute zero. However, the kinetic energy of the ground state cannot be removed. In the present era, Scientists and technologists daily achieve temperatures close to absolute zero, where matter exhibits quantum effects like superconductivity, superfluidity, Bose-Einstein condensate, etc.

Absolute Zero Equations

While making a thermometer using a tube wall, we need to mark a scale on the tube wall with numbers on it. These numbers present a temperature scale. 

A temperature scale is a way to measure temperature relative to a starting point viz: 0 or zero, and a unit of measurement.

Here, zero represents the freezing point and 100 represents the boiling point. The units of measurement are:

• Degree Celsius

• Degree Fahrenheit

• Kelvin

The absolute temperature scale that agrees to the Celsius scale is called the Kelvin (K) scale. 

The absolute scale that is analogous to the Fahrenheit scale is called the Rankine (R) scale. The zero points on both absolute scales (Celsius and Fahrenheit) represent the same physical state. The relationships between the absolute and relative temperature scales are described in the following equations:

1. Kelvin to Celsius

K = °C + 273.15

°C = K – 273.15

2. Rankine to Fahrenheit

R = °F + 460

°F = R – 460

How to Start Studying the Absolute Zero 

You can start studying the Absolute Zero - Explanation, Equations, and FAQs from Vedantu’s official website. It is one of the most important concepts of Physics, which requires a lot of your time and attention. You can use our online learning platform to revise the concept of absolute zero and thermodynamics. Here are some tips on how you should prepare this concept: 

• Go through the entire chapter from your textbook to get an idea of what absolute zero is and why it is important in the world of Physics. 

• Use the exercise questions given at the back of the chapter in your textbook to test your knowledge and see whether you have understood the concept of absolute zero. 

• While studying the Absolute Zero - Explanation, Equations, and FAQs, write down all the important points to make a summary of the concept. This summary will come in handy during later revisions. 

• Refer to the guides and reference books to gain a better understanding of absolute zero. These reference books contain a number of questions based on the same pattern as your exam. You can practice the questions based on Absolute Zero - Explanation and Equations and strengthen your grasp of the concept. 

• You can use Vedantu’s e-learning platform to revise the concept of Absolute Zero - Explanation, Equations, and FAQs. Our experienced teachers have explained the topic in a simple language to help you understand it easily. 

• Read the explanation and equation of absolute zero thoroughly before you move to the exercise questions. 

Benefits of learning the concept of Absolute Zero

Learning the concept of Absolute Zero - Explanation, Equations and FAQs will be really beneficial for you. It gives you a better understanding of thermodynamics and temperature, which are important topics of Physics. Here are some advantages of learning the Absolute Zero - Explanation, Equations, and FAQs:   

• By Studying the Absolute Zero - Explanation, Equations, and FAQs, you can improve your understanding of thermodynamics. 

• The Absolute Zero - Explanation, Equations, and FAQs will help you understand the concept of the Kelvin scale as well.

• Once you Go Through the Absolute Zero - Explanation, Equations, and FAQs thoroughly, you will understand the importance of this concept in Physics.  

• The Absolute Zero - Explanation, Equations, and FAQs available on Vedantu will be enough to revise the entire concept and score well in the Physics exam. 

• The Absolute Zero - Explanation, Equations, and FAQs provided by Vedantu will make it easier for the students to maintain a strong grasp of the topic.