What is a travelling (progressive) wave?
A travelling wave can be described by plotting its amplitude as a function of distance from the source or displacement at a fixed point over time.
What happens when two waves meet?
They interfere and superpose to form a resultant wave.
What determines the resultant wave when two waves meet?
The amplitudes of the two waves combine, producing a resultant that may be greater or less.
What is the principle of superposition?
The total displacement at a point is equal to the sum of the individual displacements of the waves.
What is constructive interference?
It occurs when two waves meet crest to crest, producing a larger resultant amplitude.
How is the resultant displacement calculated?
By adding the displacements of the two waves together.
What happens to amplitude in constructive interference?
The amplitudes add together.
What is destructive interference?
It occurs when a crest meets a trough, cancelling the waves.
What happens to amplitude in destructive interference?
The waves cancel, producing zero or reduced amplitude.
What does Young’s Double Slit Experiment demonstrate?
It demonstrates interference of light waves.
When does maximum intensity occur in Young’s experiment?
When two wave crests meet (constructive interference).
When does minimum intensity occur?
When a crest meets a trough (destructive interference).
What pattern is formed in Young’s experiment?
What pattern is formed in Young’s experiment?
What does a bright fringe represent?
What does a bright fringe represent?
What affects the position of bright fringes?
The wavelength of light, slit separation, and distance to the screen.
What happens to fringe spacing when wavelength increases?
What happens to fringe spacing when wavelength increases?
What conclusion can be made when comparing different wavelengths?
Different wavelengths produce different fringe separations.
What does monochromatic mean?
Light of a single wavelength.
What is required for interference patterns to form?
What is required for interference patterns to form?
What are coherent waves?
Waves that have a constant phase relationship.
What are incoherent waves?
Waves with a random or changing phase relationship.
Why are coherent waves important for interference?
They maintain a stable interference pattern.
How is interference used in optometry?
It is used in anti-reflective coatings.
What is the purpose of interference in anti-reflective coatings?
To reduce reflected light using destructive interference.
