wave qualities

• waves transfer energy in...

  In the direction they are travelling
• wave


  a disturbance that transfers energy from place to place
• wavelength


  the distance between two corresponding parts of a wave (m), which pitch depends on
• amplitude


  height of wave, which volume depends on
• oscillations


  vibrations of a wave
• crest


  point of maximum positive displacement from rest position
• trough


  point of maximum negative displacement from rest position
• equilibrium (rest position)


  a state in which opposing forces or influences are balanced.
• mechanical waves


  waves that require a medium through which to travel and cause vibrations of particles in a solid, liquid or gas and must have a medium to travel through
• transverse wave


  a wave in which the particles of the medium move perpendicularly to the direction the wave is traveling
• do traverse waves need a medium to continue moving forward?

  - sound and water waves do need a medium

  - electromagnetic waves do not need a medium
• traverse wave diagram

  
• longitudinal wave


  a wave in which the vibration of the medium is parallel to the direction the wave travels
• do longitudinal waves need a medium to continue moving forward?


  yes
• longitudinal wave diagram

  
• compression


  when waves are closest together
• rarefraction


  when speed and wavelength change
• amplitude determines the ... of a sound

  volume
• frequency determines the ... of a sound

  pitch
• frequency


  the number of waves produced in a given amount of time
• formula for frequency using period

  T = 1/f
• wave speed


  the distance travelled each second by the wave (m/s)
• wave speed (m/s) =

  frequency (Hz) x wavelength (m)
• wave speed formula


  v=fλ
• wave speed formula triangle

  
• wave period


  time it takes to complete one wave cycle
• wave cycle


  the wave from the point of origin to the next point of origin
• human hearing range


  20-20,000 Hz
• ultrasound


  sound waves with frequencies above 20,000 Hz.
• ultrasound purposes


  - produce images of foetuses/organs inside the body (safer than x-ray)

  - clean jewellery
• distance =


  distance = speed x time
• angle of reflection =

  angle of incidence
• specular reflection


  a reflection produced by a smooth surface in which light rays are reflected in a single direction
• diffuse reflection


  reflection of light on a rough surface, where light rays are scattered
• white light


  mixture of all the colours in the visible spectrum
• colours on visible light spectrum

  red, orange, yellow, green, blue, indigo, violet
• objects that transmit light

  transparent/translucent
• objects that absorb light

  opaque
• convex lens


  - a lens that is thicker in the centre than at the edges

  - makes light rays refract and converge at a point
• convex lenses create ... images

  - real OR virtual

  - inverted OR right way up

  - magnified OR diminished