Thermal energy is energy associated with random motion of molecules. It is indicated by temperature which is the measure of the relative warmth or coolness of an object.
A temperature scale is determined by choosing two reference temperatures and dividing the temperature difference between these two points into a certain number of degrees.
The two reference temperatures used for most common scales are the melting point of ice and the boiling point of water.
- On the Celsius temperature scale, or centigrade scale, the melting point is taken as 0°C and the boiling point as 100°C, with the difference between them being equal to 100 degrees.
- On the Fahrenheit temperature scale, the melting point is taken as 32°F and the boiling point as 212°F, with the difference between them being equal to 180 degrees.
It is important to realize, however, that the temperature of a substance is not a measure of its heat content, but rather, the average kinetic energy of its molecules resulting from their motions.
Below is a 6-ounce cup with hot water and a 12-ounce cup with hot water at the same temperature.
- Do they have the same heat content?
- Do they have the same amount of energy?
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