Frequency
the amount of oscillations in a second
amplitude
the maximum displacement of a wave from equilibrium
wavelength
distance between a point on one wave to the identical place on the adjacent wave
phase
what point of the cycle a wave is in
displacement
distance from equilibrium
period
time taken for one complete oscillation
cycle
one complete repetition of the wave pattern
what are the 3 key equations
F = 1/T
V = F * WL
PD = (diff in WL/WL) * 360
what is phase difference
a comparison of the point in a waves cycle measured as an angle.
phase-in step
peaks and troughs align so PD is 0
anti-phase
peaks align with the troughs so PD is 180* (half a wavelength)
intensity
energy per second transferred per unit area
what are the 2 intensity equations
I = P/A
I = KA^2
as amplitude is related to the energy the wave transfers
Refractive index
Compares the speed of waves in a material to their speed in air.
Refractive index formula
N=C/Cs
What are the important formulas used for snells law?
N1sin(i)=N2sin(r)
Sin(i)/sin(r)=N2/N1
Total internal reflection
When all light energy is reflected within an object, it happens when the angle of incidence exceeds the critical angle and when the substance has a larger refractive index then the other.
How do you calculate the critical angle?
Sin(critical angle) = N2/N1
Propagation direction
Waves carry energy from one place to another along a certain direction
Critical angle
The angle of incidence at the boundary between two media that will produce an angle of refraction of 90
Polarisation
The phenomenon where oscillations of a transverse wave are limited to only one plane
Plane polarised
Transverse wave in which the oscillations are limited to only one plane
Partially polarised
Transverse wave in which there more oscillations in one particular plane, but the wave is not completely plane polarised - occurs when transverse waves reflect off a surface.
