Waves Flashcards
What is a progressive wave?
A wave that transfers energy from one place to another without transfering material
What is a stationary wave/
A wave that doesn’t transfer energy from one place to another
What is meant by displacement?
The distance and direction of a particle from the equilibrium position
What is meant by amplitude?
The maximum displacement of a particle on a wave from the equilibrium position
What is meant by time period?
The time taken for i whole wave cycle
What is meant by frequency?
The number of whole wave cycles to pass a given point in 1 second
What is a longitudinal wave?
A wave in which the particle oscillations are parallel to the direction of energy transfer (direction of travel)
What is a transverse wave?
A wave in which the particle ossicilations are perpendicular to the direction of travel
What does it mean if a wave is polarised?
The vibrations of the field are only in 1 plane
What is meant by phase difference?
The amount that one wave lags behind another
What is path difference?
The amount by which the path travelled by one wave is longer than the path travelled by another wave
What is monochromatic light?
Light of a single wavelength (frequency)
What is meant by a coherent source?
Waves from the source have a constant phase difference, and the same frequency
What are the 2 conditions of total internal reflection?
1- the refractive index of the first material must be greater than the refractive index of the second
2- the angle of incidence must be greater than the critical angle
What is modal dispersion?
When light rays enter the optical fibre at different angles, cause it them to take different paths down the fibre and therefore causing pulse broadening
