Properties of waves

• Electromagnetic spectrum

  the range of wavelengths that light can exist in.
• Luminous body

  a body that emits light
• Non luminous body

  does not emit light, but reflects, or absorbs it
• Incandescent body

  object that emits light when it is heated.
• rectilinear propagation

  Tendency of light to travel in a straight line.
• Transparent object

  Transmits light, while it absorbs some as well.
• Translucent object

  Scatters and transmits light but does not allow objects to be clearly seen through them.
• Opaque object

  Absorbs or reflects specific wavelengths of light.
• Shadows

  Forms when an opaque object is placed in the path of light.
• Umbra

  Total shadow
• Penumbra

  partial shadow
• First person to try to measure speed of light

  Galileo
• Person who figured out light had a speed

  Olaus roemer
• speed of light

  3.00 x 10^8 m/s
• Equation for speed of light

  C=d/t
• Wave

  Transfer of energy in the form of a disturbance propagating through a medium.
• Transverse waves

  Occurs when vibration of the medium is perpendicular to the direction of the energy transfer.
• Crest of wave

  Maximum position of transverse wave
• Trough of wave

  Minimum position of a transverse wave
• Amplitude

  Maximum displacement from the equilibrium/rest position
• Wavelength

  Distance between successive crests or troughs
• Longitudinal waves

  Occur when the medium vibrates parallel to the direction of energy transfer.
• Compressions

  the regions of a longitudinal wave where the particles in the medium are closest together
• Rarefactions

  -The part of a longitudinal wave where the particles of the medium are farther apart.
• Pulse

  Wave with short duration
• Cycle

  One oscillation (or passing of a wave)
• Frequency (f)


  Number of cycles passing past a point in a given time unit.
• Period (T)


  Time required for a full wave to pass a point
• universal wave equation


  v = fλ
• Transmission

  process of a wave transferring its energy from one medium to another medium.
• Fixed end reflection

  Initial crest will become a trough after reflection
• Damping

  When amplitude of reflected wave is smaller than incident wave
• Free end reflection

  Initial crest will stay a crest and vice versa.
• Interference

  When two or more waves act simultaneously on a medium.
• principle of superposition

  when two or more waves pass through each other, the resulting disturbance at a given point in the medium is found by adding the individual displacements each wave would have caused.
• Constructive interference

  occurs when the resulting disturbance larger than the individual disturbances. This process occurs when two crests or two troughs meet.
• Destructive interference

  occurs when the resulting displacement is smaller than the individual displacements.

  This process occurs when a crest and a trough meet.
• Standing wave

  An interference pattern consisting of both maximum constructive and destructive interference. the waves interfere in such a way that it appears as if the wave does not move along the string.
• Nodes

  The places with destructive interference. Are at rest position
• antinodes.

  The places with constructive interference. Look like crests and troughs.