Physics

• Transverse pulse


  A pulse in which the particles of the medium move at right angles to the direction of motion of the pulse
• Pulse


  • A single disturbance in a medium
• Pulse


  • Crest
  • Trough
• Amplitude


  The maximum disturbance of a particle from its rest (equilibrium) position
• Pulse length


  Distance between the start and end of a pulse
• Superposition


  The algebraic sum of the amplitudes of two pulses that occupy the same space at the same time
• Interference


  When two or more pulses (and waves) interact with each other in the same space and at the same time
• Interference


  • Two pulses meet on opposite sides of the rest position
  • Results in a pulse with a smaller amplitude
  • After overlapped, continue in original directions with original amplitudes
• Destructive interference


  The phenomenon where the crest of one pulse overlaps the trough of another, resulting in a pulse of reduced amplitude
• Constructive interference


  • Two pulses meet each other on the same side of the rest position
  • Results in a pulse with a greater amplitude
  • After overlapped, continue in original directions with original amplitudes
• Constructive interference


  The phenomenon where the crest of one pulse overlaps the crest of another to produce a pulse of increased amplitude
• Crest


  Highest point (peak) on a wave
• Trough


  Lowest point on a wave
• Wavelength


  The distance between two successive points in phase
• Transverse waves

  • Water waves
• Transverse waves


  • Crest
  • Trough
  • Direction of travel
  • Wave height
  • Wavelength
• Points in phase have exactly the same movement at the same time and are equal distances from the equilibrium position
• Points out of phase do not have exactly the same movement at the same time and are not necessarily equal distances from the equilibrium position
• Wave speed


  The distance travelled by a point on a wave per unit time
• Wave equation


  1. v = speed (m/s)

  2. Ax = distance (m)

  3. At = time (s)
• f


  Frequency (Hz)
• λ


  Wavelength (m)
• The frequency of a wave is determined by the source
• Longitudinal wave


  A wave in which the particles of the medium vibrate parallel to the direction of motion of the wave
• Producing a longitudinal wave in a slinky

  1. Causing a single back and forth movement, ending at the original position

  2. Causing a series of consecutive backwards and forwards movements
• Longitudinal wave

  Series of consecutive backwards and forwards movements
• Longitudinal wave

  • Every particle in the spring moves from its rest position in the direction of propagation of the wave and then returns to its rest position
• Compression


  A region of high pressure in a longitudinal wave
• Rarefaction


  A region of low pressure in a longitudinal wave
• Wavelength


  The distance between two consecutive compressions or rarefactions
• Part where spirals are close together

  • Compression
• Where the spring is stretched


  • Rarefaction
• Frequency


  Number of (compressions) waves that move past a point per second
• Period


  Time that one complete wave takes to move past a fixed point
• Wavelength


  Distance between any two consecutive points that are in phase
• Frequency


  Inversely related to period
• Sound


  • Propagated by vibrations
  • Needs a medium
• Speed of sound


  • Travels slower than light
  • Speed of sound in air at 0°C is 331 m
  • Speed of sound in air at 20°C is 343 m/s
• Sound waves are pressure waves
• Speed of sound


  • Determined by the type of medium
  • Travels fastest in solids, less fast in liquids, and slowest in gases