Waves

Waves

1. Waves may be either transverse or longitudinal.

   • Electromagnetic waves are transverse, sound waves are longitudinal and mechanical waves may be either transverse or longitudinal.
   • Radio waves, microwaves, infrared and visible light can be used for communication. Knowledge and understanding of waves used for communication is limited to sound, light, microwaves, radio waves and infrared waves

2. All types of electromagnetic waves travel at the same speed through a vacuum (space).

3. Electromagnetic waves form a continuous spectrum.

   • Longitudinal waves show areas of compression and rarefaction.

4. Waves undergo a change of direction when they are refracted at an interface.

   • All waves obey the wave equation: v = f x λ v is speed in metres per second, m/s f is frequency in hertz, Hz λ is wavelength in metres, m

5. Waves can be reflected, refracted and diffracted.

   • Significant diffraction only occurs when the wavelength of the wave is of the same order of magnitude as the size of the gap or obstacle. Waves are not refracted if travelling along the normal.