Waves
The Wave Equation
V = Velocity
F = Frequency
λ = Lamda
V = λ x F (important formula to remember)
Refraction is the change of a direction when a wave passes through two mediums. How much a wave is refracted is depended on the speed of the wave and the initial direction. If it reaches the interface between the materials at an angle one side of the wave will reach the second material first, and therefore slow down earlier. With one side of the wave going slower the whole wave will pivot towards that side.
We know that light refracts when it goes from one medium to another but why? Light travels at 300,000 km a second, however in glass it travels 40% slower meaning glass has refractive index of 1.4. Why do photons move slower in a denser material?
Reflection
The angle of incidence is equal to the angle of reflection.
The real answer is that photons follow every single possible path and then are distributed out the other end. When all the interferences with the atoms are added together they combine to the final wave on the far side. This process of following paths and combining wave takes longer and refracts the light. This is an example of superposition.
What is frequency, velocity and lambda?
Frequency is the amount of waves per second.
Velocity is the speed of something in a given direction.
Lambda is the wave length.
Longitude and Transversal waves
Longitude: A longitudinal wave is a wave in which particles of the medium move in a direction parallel to the direction that the wave moves.
Transversal waves are always characterized by particle motion being perpendicular to wave motion.
Refractive index Different materials have different refractive indexes. The amount light refracts is depended on the refractive index.
sin i divided by sin r = n (refractive index)
Extra Vocab
Peak/Crest = The highest point of the wave.
Photon = a particle that travels light
Amplitude = the maximum extent of a vibration or oscillation, measured from the position of equilibrium.
C = speed (specifically of light)
Refraction