Absolute temperature is a measure of temperature that uses absolute zero as its zero point. The absolute temperature scale is also known as the Kelvin scale. The SI unit for absolute temperature is the Kelvin (K).

**Absolute zero** is the temperature at which all thermal energy is removed from a system. It is the lowest temperature that can be reached, and is equivalent to -273.15°C (-459.67°F).

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## What is the absolute temperature?

Absolute temperature is temperature measured using the Kelvin scale where zero is absolute zero. The zero point **is the temperature at which particles of matter have their minimum motion and can become no colder (minimum energy).**

The **Kelvin scale** is an absolute temperature scale that uses absolute zero as its null point. Zero on the Kelvin scale (written “0 K”) corresponds to absolute zero, the complete absence of thermal energy.

Absolute zero is often thought of as the coldest possible temperature, but it is in fact only a **theoretical limit**. It is impossible to achieve absolute zero of temperature in practice. Even if all thermal motion could be stopped Dispatch, atoms would still possess a tiny amount of internal energy called the zero-point energy and thus would not be able to reach absolute zero.

**The SI unit of temperature**, the kelvin, is named in honor of the Scottish physicist who developed the concept of an “absolute” temperature scale. One kelvin is equal to 1/273.16 of the thermodynamic temperature of the triple point of water.**The Kelvin scale uses**absolute zero as its null point. Zero on the Kelvin scale (written “0 K”) corresponds to absolute zero, the complete absence of thermal energy.**Absolute zero**is often thought of as the coldest possible temperature, but it is in fact only a theoretical limit.

## How do you find the absolute temperature?

The Celsius and absolute temperature scales are related by a simple equation:

**Absolute temperature (Kelvin) = Celsius temperature + 273.15**

To convert from the Celsius scale into the absolute temperature, you add 273.15 and change °C to K. To get a temperature on the absolute scale to the Celsius scale, subtract 273.15 and change K to °C. This is normally used in the science world.

## Who defined absolute temperature?

**William Thomson (1824–1907)**, better known as Lord Kelvin, made pioneering efforts to create the modern concept of absolute (thermodynamic) temperature, counted in ‘degrees Kelvin’ in his honor.

**Kelvin was born in Belfast, Ireland**, the eldest son of James Thomson, professor of mathematics at the University of Glasgow. He was educated at home until the age of 10, when he entered Glasgow Academy. In 1834 he entered the University of Glasgow, where he studied under James MacCullagh and Dugald Stewart. He won the university’s Hamilton Medal in 1837 and graduated with highest honors in mathematics and natural philosophy in 1841.

Thomson’s studies continued at Peterhouse, Cambridge from 1841 to 1846. There he worked with William Hopkins and Peter Guthrie Tait on mathematical subjects including the kinetic theory of gases. In 1845 he published his first paper on this topic, ‘On an Absolute Thermometric Scale’.

In 1846 Thomson **was elected a fellow of Trinity College, Cambridge**. The following year he became professor of natural philosophy at the University College of Glasgow, a post he would hold for the next fifty years. It was there that he did most of his important work on electricity and thermodynamics.

In the early 1850s Thomson began investigating the nature of heat and its relationship to electricity. His famous paper ‘On a Universal Tendency in Nature to the Dissipation of Mechanical Energy’ was published in 1852. In it he proposed the ‘universal’ law that energy is always lost in any real process or change. This law is now known as the **Second Law of Thermodynamics**.

In 1854 Thomson postulated the existence of an invisible substance he called ‘radiant matter’ or ‘ether’, which was necessary for the propagation of light. His work on optics culminated in the publication of ‘Treatise on Natural Philosophy’ in 1860-71, co-written with Peter Guthrie Tait.

In 1884 Thomson formulated what is now known as **Kelvin’s Law of Thermodynamics**: that when two bodies at different temperatures come into thermal contact with each other, heat will flow from the hotter body to the colder one until both reach the same temperature.

Kelvin was elected to the Royal Society in 1851 and became its president in 1890. He was also a member of many other learned societies and associations, both in Britain and overseas. He was created a baronet in 1866 and a peer in 1892.

Lord Kelvin died in 1907 at the age of 83. He was buried in Westminster Abbey.

## What is absolute zero and absolute temperature?

**Absolute zero**, or 0 Kelvin, is the lowest possible temperature where nothing can be colder and no heat energy remains in a substance. This temperature is achievable in theory, but not in practice. In order for something to have 0 Kelvin, all of its particles would have to stop moving.

**Absolute temperature** is a measure of how far above or below absolute zero a substance’s temperature is. The Kelvin scale is the most popular absolute temperature scale, and it’s also the one used by scientists. Water freezes at 273.15 Kelvin and boils at 373.15 Kelvin.

**The Celsius** scale is another absolute temperature scale, and it’s the one more commonly used in everyday life. Water freezes at 0 degrees Celsius and boils at 100 degrees Celsius. The Fahrenheit scale is a third absolute temperature scale, and like the Celsius scale, it’s commonly used in everyday life. Water freezes at 32 degrees Fahrenheit and boils at 212 degrees Fahrenheit.

To convert from one absolute temperature scale to another, we use the following formulas:

**Kelvin (K) = Celsius (°C) + 273.15****Celsius (°C) = Kelvin (K) – 273.15****Fahrenheit (°F) = (Celsius (°C) x 1.8) + 32**

## What is absolute temperature in heat transfer?

According to the second law of thermodynamics, energy is transferred from bodies with higher temperature to bodies with lower temperature. **The absolute temperature is always positive, T > 0.** The least absolute temperature possible is the absolute zero.

#### What exactly is absolute temperature? And what does it mean in terms of heat transfer?

Absolute temperature is a measure of how hot or cold a body is, measured on a scale where the absolute zero of temperature is the lowest possible temperature. On this scale, the Celsius and Fahrenheit scales are both equal to zero at absolute zero. The Kelvin scale is the most commonly used absolute temperature scale.

In terms of heat transfer, absolute temperature is important because it determines the direction of heat flow. According to the second law of thermodynamics, **energy is transferred from bodies with higher temperatures to bodies with lower temperatures.** This is because heat always flows from hotter to colder objects, until they reach the same temperature.

When two objects are at different temperatures, **heat will always flow from the hotter object to the colder object.** The amount of heat that flows will depend on the difference in temperatures between the two objects.

The rate at which heat flows will also depend on the nature of the material itself. Some materials are better conductors of heat than others. For example, metals are good conductors of heat, while insulators are materials that do not conduct heat well.

**In conclusion**, absolute temperature is a important concept in understanding heat transfer. Heat always flows from hotter to colder objects, and the rate at which heat flows depends on the difference in temperatures between the two objects and the nature of the materials involved.

## What is the absolute temperature if it is 121 C?

The absolute temperature scale is a bit more complicated than the relative temperature scale that we use in everyday life. On the absolute temperature scale, **the coldest possible temperature** is called absolute zero. This is the point where all molecular motion ceases.

**The unit of measurement** on the absolute temperature scale is the Kelvin (K). Zero Kelvin is equal to -273.15 degrees Celsius. So, if we take our temperature of 121 C and add 273.15, we get 394.15 Kelvin.

**The absolute temperature** of 121 C is also equal to 249.8 degrees Fahrenheit.