Measuring Temperature

When we measure length, we use a ruler; when we measure time, we use a clock; and when we measure temperature, we use a thermometer.

Parts of a thermometer
If you have a fever, you can use a thermometer to measure your fever. Some thermometers allow you to measure your temperature by placing the bulb in your mouth, and another by placing the bulb in your armpits.

Thermometry is the process of measuring temperature. The first practical measurement of temperature was developed by Daniel Gabriel Fahrenheit (1686-1736). He invented the first mercury thermometer where the standardized temperature scale was in Fahrenheit.

Another temperature scale is Celcius, invented by Anders Celsius (1701-1744). The Celsius scale is known as a Universal System Unit, it is used throughout science and in most countries. Fahrenheit and Celsius are just two methods to measure temperature, there are others.

This is one of the most common method to measure temperature. The glass tube is filled with mercury or some other liquid. When the temperature increases, the fluid expands, so the temperature is measured by observing the volume of the fluid.
This is another type of thermometer called the gas thermometer.

According to the thermometer, at standard pressure, water freezes at 0°C or 32°F and water boils at 100°C or 212°F. On an average, the human body has a temperature of about 36.8°C or 98.2°F.


Heat and Temperature