Waves Flashcards
What is a wave?
A periodic disturbance of particles in a material or in space.
What is a transverse wave?
Particle oscillations are perpendicular to the direction of propagation of the wave.
What is a longitudinal wave?
Particle oscillations are parallel to the direction of propagation of the wave.
What are mechanical waves?
Oscillations of particles in a physical medium.
What are Electromagnetic (EM) waves?
Waves produced by the acceleration of charged particles, transmit through vacuum.
What is the equation of wave speed?
Speed = Frequency x Wavelength
What is the frequency of a wave?
Number of waves passing a point in one second.
What is the period of a wave?
Time for a full cycle.
What is unpolarised light?
Waves at all different possible planes at 90 degrees to the source.
What is polarised light?
Wave is only oscillating in one plane.
What is superposition?
Two or more waves overlap, the resultant displacement at a point is the sum of the individual waves at that point (waves add up).
What is constructive interference?
Waves have the same sign displacement when they overlap (reinforcement).
What is destructive interference?
Waves have opposite sign displacement where they overlap (cancellation).
What is diffraction?
Wave spread out after passing through a gap.
What are coherent waves?
Two waves with the same frequency and wavelength and have a constant phase difference.
