| A | B |
|---|
| Electromagnetic waves | Produced by accelerating charges |
| Speed of light | 3 x 10^8 m/s |
| Symbol for speed of light | c |
| Photons | Packets of electromagnetic energy |
| Photoelectric effect | Electrons emitted as a result of light shing on a metal |
| Intensity | Rate of wave energy flowing through a given area |
| Herschel | Used a prism to separate wavelengths of light; discoved infrared radiation |
| Young | Showed that light behaves like a wave (1801) |
| Einstein | Proposed photons (1905) |
| Michelson | Measured the speed of light with rotating mirrors |
| Electromagnetic spectrum | Includes: radio waves, infrared, visible, ulraviolet, x-rays and beyond |
| X-rays | Can kill or damage human tissue |
| Gamma rays | High energy, short wavelength, large penetrating ability |
| Microwaves | Short wavelength radio waves |
| Visible light | Wavelengths from 400 nm to 750 nm |
| Radio waves | Longest wavelength in E&M spectrum |
| Infrared waves | Used as a heat source |
| Transparent | Allows light to pass through |
| Translucent | Scatters light |
| Opaque | Absorbs or reflects the light that strikes it |
| Regular reflection | Light strikes a smooth surface |
| Diffuse reflection | Light strikes a rough surface |
| Refraction | Light bends as it changes media |
| Polarized light | Vibrates in only one direction |
| Scattering | Light is redirected as it passes through a medium |
| Dispersion | White light separates into colors |
| Primary colors | Red, green and blue |
| Secondary color | Combination of primary colors |
| Complimentary colors | Combine to form white light |
| Pigment | Absorbs some colors, reflects others |
| Luminous | Objects that give off their own light |
| Incandescent | Objects get hot enough to glow |
| Florescence | Absorbs at one wavelength and emits at a longer wavelength |
| Phosphor | Solid material that emits light by florescence |
| Laser | Generates a beam of coherent light |
