define temperature as the measure
of thermal energy and describe the way it is measured.
How
do we measure thermal energy?
Thermal energy is measured using a thermometer.
We use thermometers to find the temperature of a substance. Temperature
is actually a measure of the substance's thermal energy.
Temperature
and Thermal Energy
Inside a thermometer is a liquid (most
often alcohol) that, when heated, expands and rises through
the thermometer. We read this as an increase in temperature.
This also indicates an increase in thermal energy. When thermal
energy is decreased, the liquid contracts and falls through
the thermometer. We read this as a decrease in temperature and
thermal energy.
Click the thermometer
to see how thermal energy affects temperature.
You can see that as thermal
energy rises, so does the temperature. As thermal energy falls,
so does the temperature. Remember:
more thermal energy
= higher temperature
less thermal energy
= lower temperature
Temperature
Scales
There are three main scales that the world uses
to measure temperature: Fahrenheit (ºF), Celsius (ºC), and the Kelvin
Scale (K). We're going to focus on the Fahrenheit and Celsius scales.
Each scale uses different temperatures to measure the boiling point
and freezing point of water. Below is a table that has them temperatures
as well as some others that show how the scales differ.
