The bending of light as it goes from one medium into another.
Refraction
A device that refracts light so the rays converge or diverge.
A lens
Complete bounce-back of light inside a material.
Total internal reflection
A wave changing direction around an obstacle or slit.
Diffraction
Newton said light was made of these particles.
Corpuscles
Light bends because this changes from one medium to the next.
Speed
Where parallel rays meet after a converging lens.
The focal point
The incident angle that sends the refracted ray along the boundary.
The critical angle
The bright middle band of a diffraction pattern.
Central maximum
Young’s double-slit experiment supported this view of light.
Wave
Going from air into glass, this shortens while frequency stays the same.
Wavelength
Farsightedness; nearby objects focus behind the retina.
Hyperopia
If the incident angle is larger than the critical angle, the light does this.
Reflects entirely inside
A set of many slits that spreads light into colors.
A diffraction grating
Light through two slits makes bright and dark bands because it does this with itself.
Interferes
The ratio of light’s speed in vacuum to its speed in the material.
Index of refraction
Nearsightedness; distant objects focus in front of the retina.
Myopia
Hot air near a road can make one of these because its index is lower.
A mirage
An instrument’s ability to tell two nearby sources apart.
Resolving power
Einstein explained the photoelectric effect with these packets of light.
Photons
Separating mixed colors into their wavelengths.
Dispersion
In a compound microscope, the lens nearer the specimen.
Objective
Diamonds sparkle because light is trapped this way until it can leave the top.
Total internal reflection
Each element has its own unique one of these through a grating.
Spectrum
When light hits a metal surface and knocks electrons out.
The photoelectric effect