Define amplitude
The maximum magnitude of the displacement
Define wavelength
The length of one whole wave cycle from crest to crest
Define wave speed
the speed at which a point of constant phrase moves
Define wave frequency
The number of cycles per second passing a given point
Define time period
The time taken for a whole cycle to complete
Define a longitudinal wave
It is where the vibrations are parallel to the direction in which the wave travels
State the equation linking frequency and time period
f=1/T
Define a transverse wave
The wave vibrations are perpendicular to the direction of energy transfer
Define phase difference
The amount one wave lags behind another
Define phase
a measurement of the position of a certain point along the wave cycle
Define displacement
how far a point on the wave has moved from its undisturbed position
What equation link speed, frequency and wavelength?
v = f x λ
Define intensity
Energy per unit time
Define a plane polarised wave
oscillations are in one direction only and are
perpendicular to the direction of wave propagation
Define a progressive wave
is a transfer of energy as a result of oscillations
State difference between progressive wave and stationary waves
1) a progressive wave transfers energy
2) a progressive wave transfers shape
State the principle of superposition waves
when 2 or more waves meet
Define a diffraction wave
wave fronts spread out after passing through a gap or around an obstacle
State two features of a stationary wave
1) energy is trapped in pockets
2) there are nodes
Explain IR
infra red is part of the e-m spectrum and longer λ than the visible light
Define interference
when two waves meet at a point there is a change in overall intensity
Define coherence
constant phase difference between the waves
