Polarisation and Transverse Waves

Polarisation and Transverse Waves

1. EM Waves

   • All EM waves are transverse
   • Transverse waves have vibrations at a right angle to the direction of travel
   • Have displacement against distance graphs
   • Or displacement against time graphs

2. Polarised Waves

   • Oscillate in one direction
   • Polarising filters block out vibrations in other planes
   • If 2 filters are at right angles to each other, the wave will be cancelled out
   • Only happens with transverse waves

3. Light

   • When it reflects it is partially polarised
   • The intensity of light changes with the orientation of the filter

4. Uses of Polarised Light

   • TV aerials
   • Communications satellites
   • Bees
   • CD players
   • Polaroid sunglasses