Absolute Zero

Absolute zero is said to be a temperature, which is a physical quantity. A substance's temperature represents a measurement of its warmth or coldness. Every object or matter that exists in the universe has a temperature.

Temperature can also be described as a measure of thermal energy present inside a body. For temperature measurements, the kelvin serves as the standard unit. Temperature and heat are two very different things.

The scales by which temperature is measured are:

• Celsius scale (also called Centigrade scale)

• Kelvin scale

• Fahrenheit scale

What is Meant by Absolute Zero?

Absolute zero is the lowest possible temperature, where the heat in a body is zero. Absolute zero is also called the zero-kelvin temperature, as it measures zero on the Kelvin scale.

The fundamental particles present in nature show very little vibration at absolute zero temperature. Absolute zero is measured as:

• -273°C on the Celsius scale

• -459.76°F on the Fahrenheit scale

The Behavior of Gases at Absolute Zero

When the temperature around gas particles lowers, the particles move more slowly. At absolute zero:

• Gas particles stop moving but still retain some energy.

• Heat can never be completely removed from a substance.

The concept of absolute zero arose while studying the behavior of gases at different temperatures.

Conversion of Temperature from One Scale to Another

Formulas:

• k=°C+273k = \text{°C} + 273k=°C+273

• °C=k−273\text{°C} = k - 273°C=k−273

Examples:

Celsius to Kelvin:

• 30°C → k=30+273=303 Kk = 30 + 273 = 303\,Kk=30+273=303K

• 40°C → k=40+273=313 Kk = 40 + 273 = 313\,Kk=40+273=313K

• 50°C → k=50+273=323 Kk = 50 + 273 = 323\,Kk=50+273=323K

• 60°C → k=60+273=333 Kk = 60 + 273 = 333\,Kk=60+273=333K

Kelvin to Celsius:

• 400 K → °C=400−273=127 °C\text{°C} = 400 - 273 = 127\,°C°C=400−273=127°C

• 500 K → °C=500−273=227 °C\text{°C} = 500 - 273 = 227\,°C°C=500−273=227°C

• 600 K → °C=600−273=327 °C\text{°C} = 600 - 273 = 327\,°C°C=600−273=327°C

• 700 K → °C=700−273=427 °C\text{°C} = 700 - 273 = 427\,°C°C=700−273=427°C