Heat:
- Heat is a form of energy that is transferred from one body to another as a result of a difference in temperature.
- It flows from a hotter to a colder body.
Temperature:
- Temperature is a measure of how hot or cold a body is.
- It tells us the degree of hotness or coldness of a body.
Critical temperature:
The critical temperature is the temperature above which a substance cannot exist as a liquid, no matter how much pressure is applied.
Scales of temperature:
There are three main scales of temperature: Celsius, Fahrenheit, and Kelvin.
a. Celsius:
The Celsius scale, also known as the Centigrade scale, is a temperature scale in which 0°C represents the freezing point of water and 100°C represents the boiling point of water at standard atmospheric pressure.
b. Fahrenheit:
The Fahrenheit scale is a temperature scale in which 32°F represents the freezing point of water and 212°F represents the boiling point of water at standard atmospheric pressure.
c. Kelvin scale or absolute scale:
- The Kelvin scale, also known as the absolute scale, is a temperature scale in which 0 K represents absolute zero, which is the temperature at which all matter has zero thermal energy.
- The Kelvin scale is used in scientific and technical applications and is based on the Celsius scale, with the difference being that it starts at absolute zero.