3.1. Temperature and Energy Changes

Temperature is a property that we are broadly familiar with through our everyday experiences. In everyday life we typically measure temperature in Celsius (other than the Americans reading this!) - a scale built upon the freezing and boiling point of water. In Physics, we instead more commonly use the Kelvin scale - a much more useful measurement in science, as it starts at absolute zero (i.e. zero Kelvin).

Think about the above example discussing the temperature of deepest darkest space - what exactly does this mean? In Physics, temperature is really a measurement of the average kinetic energy of the molecules in a substance. In deepest space, this 'temperature' would therefore be due to the kinetic energy of the handful of H and He molecules flying around.

If you are unfamiliar with conversions between Celsius and Kelvin, take a look at this video (you don't need to worry about the Fahrenheit conversions for IB fortunately!).