|
The thermometer is an instrument used to measure temperature. Temperature tells you how hot or
how cold an object is, not how much heat it contains.
Air temperature is one of the most important variables used to describe the state of the atmosphere.
It is a vital component of weather reports and forecasts.
Temperature affects our daily lives and helps us determine what to wear, what activities we should
avoid, and what actions we should take to minimise risks to our health.
Temperature is important to many people, especially when it is very hot or very cold.
|
- health of the old and very young can be affected.
- people working outside must know how to dress appropriately, what activities to avoid, and when
it is appropriate to stop work.
- firefighters must know when there is a greater risk of bushfires.
the instrument
The most common type of thermometer is liquid-in-glass and contains either mercury or alcohol.
A uniform diameter glass tube opens into a liquid-filled bulb at one end. The thermometer is sealed
to preserve a partial vacuum in the tube. As temperatures rise, the liquid expands and rises in the tube.
When temperatures fall, the liquid contracts and falls in the tube. |
