Units

Units

##Introduction to Units

  • Units are standard quantities used to specify measurements.
  • All physical quantities are measured in terms of units.
  • The science of waves involves units that measure properties like amplitude, frequency, wavelength, and speed.

##Amplitude Units

  • Amplitude is a measure of the maximum displacement from the equilibrium position during one wave cycle.
  • The standard unit of amplitude is the metre (m).
  • In certain contexts, other units can be used, such as decibels (dB) for sound amplitude.

##Frequency Units

  • Frequency refers to the number of complete wave cycles per second.
  • The standard unit for frequency is the hertz (Hz), where 1 Hz equals one cycle per second.
  • Other units used are kilohertz (kHz), megahertz (MHz), and gigahertz (GHz), especially in the context of radio and audio frequencies.

##Wavelength Units

  • Wavelength is the distance between two consecutive points in a wave that are in the same phase.
  • Wavelength is typically measured in metres (m), but can also be measured in nanometres (nm) and picometres (pm) for very small wavelengths such as those of light waves.

##Speed Units

  • Speed of a wave is the speed with which a wave point, such as a crest, travels.
  • Speed is usually given in metres per second (m/s).
  • In the context of light waves, speed can also be given in kilometres per second (km/s) or as a constant, the speed of light (3 x 10^8 m/s).

##Time Period Units

  • The time period is defined as the time it takes for one full cycle of the wave.
  • This is measured in seconds (s).

##Wave Number Units

  • The wave number is the spatial frequency of the wave, measured in cycles per unit distance or radians per unit distance.
  • It is typically measured in reciprocal meters (1/m).

By understanding these units and how they relate to waves, you will be able to accurately describe, measure, and predict wave behaviour.