Waves Flashcards
What equation is used to calculate the Velocity of a Wave?
Velocity = Wavelength x Frequency = Wavelength / Period V = λf = λ/t
What is Phase Difference?
A way of describing the difference in positioning of two waves or points on waves
Inphase(0° or 360° or 2π) means that they are alligned
Antiphase(180° or π) means they are completely disalligned
What is Path Difference?
The difference in distance or wavelength, which two waves have traveled.
Symbol is Δλ
What are P and S Waves?
Shock waves from Earthquakes
P-Waves are Longitudinal waves, they are faster and are felt first. (P = Primary)
S-Waves are Transverse waves they are slower and feltr second. (S = Secondary)
What is a Transverse Wave?
A wave where diplacement is perpendicular to the direction of propagation
eg. Light
What is a Longitudinal Wave?
A wave where displacement is parrallel to the direction of propagation
eg. Sound
What is Polarisation?
When the displacement of a wave is confined to a single direction.
It is only appliable to transverse waves
Uses include glare reducing lenses
What is perpendicular to a surface?
Normal Line
What connects the Angle of Incidence and Angel of Reflection?
Angle of Incidence = Angle of Reflection
What is Refraction?
The change in direction of the travel of a wave, when changing medium
What equation links the Speed of Light and Refractive Index?
Refractive Index = Speed of Light / Speed of Light in Medium
n=c/c(s)
c(s) is c with a lowercase s
What is the Speed of Light in a Vacuum?
3 x 10^8
What is Snell’s Law?
When a wave travels into a material with a higher refractive index the ray will refract toward the normal.
Into lower refractive index, refraction is away from normal
What is the equation for Snell’s Law?
nsinθ = nsinθ Refractive index(exiting medium) x Sin(angle of incidence) = Refraction index(entering medium) x Sin(angle of refraction)
What is the Critical Angle?
The angle of incidence at which the angle of refraction is 90°