Heat and temperature are different
Many people mix up heat and temperature, but they are not the same. Heat is a form of energy that flows from a hotter object to a cooler one. It is measured in joules (J). Temperature is a measure of how hot or cold an object is. It is measured in degrees Celsius (°C) using a thermometer.
How they are related
When heat energy is added to an object, the particles inside move faster and the temperature rises. When heat is taken away, the particles slow down and the temperature falls. So adding heat usually raises temperature, and removing heat lowers it.
Key idea
Heat is energy (joules, J). Temperature tells how hot something is (degrees Celsius, °C). Heat flows from high temperature to low temperature, never the other way by itself.
Why size matters
A large amount of water at 40 °C contains more heat energy than a small cup of water at the same 40 °C, even though their temperatures are equal. This is because the big body of water has many more particles storing energy.
Example
A spark from a sparkler is very hot (high temperature) but carries little heat energy, so it does not burn your hand badly. A warm bath is at a lower temperature but holds much more heat energy.
Remember
- Heat is measured in joules (J); temperature in degrees Celsius (°C).
- Adding heat raises temperature; removing heat lowers it.
- Heat flows from hot to cold on its own.