Waves - CP4

Waves - CP4

1. CP4a

   • Sea waves transfer energy to the shore, when the waves hit the land, the energy is transferred to the land and can wear it away
   • Waves on the surface of the water are transverse waves
     • Particles in the water move up and down as a wave passes - the particles are not carried to the shore
   • Sound waves also transfer energy
     • Sound waves are longitudinal waves
       • Particles in the material through which the wave is travelling move backwards and forwards as the wave passes
   • Earthquakes and explosions produce seismic waves that travel through the Earth
     • Solid rock material can be pushed and pulled (longitudinal seismic waves) or moved up and down, or side to side (transverse seismic waves)
   • Electromagnetic waves (such as light, radio waves, microwaves) are transverse waves and do not need a medium (material) to pass through
     • Waves travel at different speeds through different materials
   • A wave frequency is the number of waves passing a point each second
     • Wave frequency is measured in hertz (Hz)
       • A frequency of 1 hertz means 1 wave passing per second
       • For sound, the wave frequency determines the pitch (how high or low it sounds)
       • For light, the frequency determines the colour
   • The period is the length of time it takes one wave to pass a given point
   • The wavelength of a wave is the distance from a point on one wave to a point in the same position on the next wave, measured in metres
   • The amplitude of a wave is the maximum distance of a point on the wave away from its rest position, measured in metres
     • The greater the amplitude of a sound wave, the louder the sound
   • The velocity of a wave is the speed of the wave in the direction it is travelling