Waves

Waves

1. Longitudinal Waves

   • Vibration of the particle is parallel to the direction of travel
   • Examples are sound waves, primary seismic waves and compression waves.

2. Transverse Waves

   • Direction of vibration is perpendicular to the direction of travel
   • Examples are electromagnetic waves, secondary seismic waves and waves on a string or wire.

3. Polarisation

   • Only occurs in transverse waves
   • Occurs using a polaroid filter
     • Only allows light that vibrates in a specific direction.
   • If light is passes through 2 polaroid filters at 90 degrees to each other, no light will pass through.
   • Polarisation reduces the intensity of light

4. Key Terms

   • Displacement
     • Distance and direction from a particles equilibrium position.
   • Amplitude
     • Maximum displacement of a particle.
   • Wavelength
     • The least distance between two vibrating particles that have the same displacement and velocity.
   • Cycle
     • Maximum displacement to the next maximum displacement.
   • Period
     • The time for one complete wave to pass a fixed point.
   • Frequency
     • The number of complete waves that passes a point in a second.
   • Phase Difference
     • The phase difference between two particles of the same frequency is the fraction of the cycle between their vibrations measured in either degrees or radians.

5. Wave Properties

   • Reflection
   • Refraction
   • Diffraction

6. Stationary Waves

   • Forms when 2 progressive waves pass through each other.
   • The simplest stationary wave is known as the fundamental mode of vibration. It has a node at either end and an antinode in the middle.
   • A node is a point of no displacement and an antinode is a place of maximum displacement.

Images and files in the map