- An instrument used for measuring temperature is called a thermometer.
- A common thermometer in everyday use consists of a glass bulb (B) connected to a thin tube called Capillary tube (T) when heated.
- The capillary tube is surrounded by thick glass tube is called Stem (S).
- Celsius or centigrade scale of temperature was introduced by a Swedish Astronomer Celsius.
- Second scale of temperature is Fahrenheit and introduced by a scientist Fahrenheit.
- The third scale of temperature is Kelvin and this scale was introduced by a scientist named “Lord Kelvin”.
- The ice point (in Centigrade scale) is 0°C and boiling point of water is marked as 100°C.
- The ice point (in Fahrenheit scale) is 32°F and the boiling point of water is marked as 212°F.
- The ice point (in Kelvin scale) is 273 Kelvin and the boiling point of water is marked as 373 Kelvin.
- Expansion and contraction of solids and liquids can give rise to tremendous force.