Physics - Core Science (P1)

Physics | P1 | Energy transfer by heating | 1.1 Infared radiation | 1.2 Surfaces and radiation

• Infared radiation is energy transfer by electromagnetic waves.
• Infared waves are part of the electromagnetic spectrum.
• We can detect infared radiation with our skin - it makes us feel warm.
• All objects emit (give off) infared radiation.
• The hotter the object, the more infared radiation it emits.
• Infared radiation can travel through a vacuum, for example space.
• Infared does NOT involve particles like the other forms of radiation.
• Matt surfaces emit and absorb more infared radiation than shiny surfaces.
• Darker objects emit and absorb more infared radiation than lighter objects.

                Matt black                 Shiny black                Matt white               Shiny white

Physics | P1 | Energy transfer by heating | 1.3 States of matter

• 3 states of matter: Solid, Liquid, Gas. We can make a substance change between these states by heating or cooling it.
• Solid - The particles vibrate about fixed positions. Fixed shape and volume. Particles arranged in ordered rows and columns. Very close together.
• Liquid - The particles are close together but can move around at random. Fixed volume. Takes the shape of its container.
• Gas - The particles are far apart and can move quickly at random. Fills avaliable space. Spreads out.

                         Solid                          Liquid                        Gas