Refraction, diffraction and interference Key Terms

sustained interference

A condition where two or more coherent waves overlap and produce a stable pattern of constructive and destructive interference.

coherent sources

Sources of waves that maintain a constant phase relationship, essential for producing sustained interference patterns.

Path Difference

The difference in distance traveled by two waves arriving at a point, which affects the interference pattern observed.

Phase Difference

The difference in phase angle between two waves at a given point, which determines whether they interfere constructively or destructively.

fringe spacing

The distance between adjacent bright or dark fringes in an interference pattern, determined by the wavelength of light and the geometry of the slits.

double-slit experiment

An experiment that demonstrates the wave nature of light through the creation of an interference pattern when coherent light passes through two closely spaced slits.

interference

The phenomenon that occurs when two or more waves superpose to form a resultant wave of greater, lower, or the same amplitude.

fringe spacing

The distance between adjacent bright or dark fringes in an interference pattern, determined by the wavelength of light and the geometry of the experimental setup.

Diffraction

The bending of waves around obstacles and openings, which occurs when the size of the obstacle or aperture is comparable to the wavelength of the wave.

Aperture

An opening or hole through which waves pass, affecting the diffraction pattern produced by the waves.

Diffraction

The bending of waves around obstacles and openings, which depends on the wavelength and the size of the aperture.

Wavelength

The distance between successive crests of a wave, typically measured in meters, which influences the extent of diffraction.

diffraction grating

An optical component with a pattern of closely spaced slits that disperses light into its constituent wavelengths, allowing for the analysis of spectra.

path difference

The difference in distance traveled by two waves arriving at a point, which determines the interference pattern observed.

Diffraction

The bending of waves around obstacles and the spreading of waves when they pass through an aperture.

Refraction

The change in direction of a wave as it passes from one medium to another due to a change in its speed.

Refraction

The bending of a wave as it passes from one medium to another due to a change in its speed.

Snell's Law

The relationship between the angles of incidence and refraction, defined by the equation n1 * sin(θ1) = n2 * sin(θ2), where n is the refractive index.

Snell's Law

The relationship between the angles of incidence and refraction, given by the formula n1 * sin(θ1) = n2 * sin(θ2), where n is the refractive index and θ is the angle.

Refractive Index

A dimensionless number that describes how fast light travels in a medium compared to vacuum, calculated as n = c / v, where c is the speed of light in vacuum and v is the speed of light in the medium.

critical angle

The angle of incidence above which total internal reflection occurs, calculated using Snell's law.

Snell's law

The relationship between the angles of incidence and refraction, given by n1 * sin(θ1) = n2 * sin(θ2), where n is the refractive index.

total internal reflection

The phenomenon that occurs when a wave traveling through a medium hits a boundary at an angle greater than the critical angle, resulting in the wave being completely reflected back into the medium.

critical angle

The minimum angle of incidence at which total internal reflection occurs, defined by the relationship between the refractive indices of the two media.