Waves (definitions) Flashcards
Progressive Wave
A transfer of energy, as a result of the oscillations of the medium or particles through which energy is traveling.
Longitudinal Wave
Wave vibrations are parallel to the Wave direction.
Transverse Wave
Wave vibrations are perpendicular to the wave direction.
Displacement (Waves)
The distance of a point on a the wave from the equilibrium position.
Amplitude (Waves)
The maximum displacement of any wave from the equilibrium position.
Wavelength (Waves)
The distance from any point on the wave to the next subsequent point in phase.
Wave Speed (Waves)
The speed at which the energy is transmitted by the wave.
Frequency (Waves)
The number of oscillations at a point per unit time.
Period (Waves)
The time taken for one complete oscillation.
Interference
When two waves meet at a point, there is a change in the overall displacement.
Principle of Superposition
When two waves interfere at a point, the resultant displacement is the sum of the individual displacements.
Path Difference
The extra distance travelled by a wave compared to another.
Coherence
A constant phase difference between waves.
Coherent Sources
Source of waves which have a constant phase difference.
Diffraction
The spreading out of a wave after passing through a gap or around an obstacle.
Plane Polarisation
Plane polarised waves oscillate in one plane only.
Intensity
The rate of energy transmitted per unit area at right angles to the direction of propagation; (W/m^2).
Standing Wave
A wave consisting of nodes and antinodes which does not transfer energy.
Node
A point where the amplitude of vibrations is always zero.
Antinode
A point where the amplitude of vibrations takes the maximum possible value.
