| A | B |
|---|
| visible spectrum | the wavelengths of light that can be seen with the human eye. |
| invisible spectrum | wavelengths of light that cannot be seen by the human eye |
| ultraviolet light | light in the invisible spectrum with wavelength shorter than violet - high levels harmful to living things |
| x-rays | energetic waves w/ wavelengths shorter than ultraviolet |
| law of reflection | the angle of incidence is equal to the angle of reflection |
| incident ray | the ray of light that hits a surface |
| reflected ray | a ray of light that has bounced off a surface |
| normal line | an imaginary line drawn at 90 degrees to the surface |
| angle of incidence | an angle measured between the incident ray and the normal line |
| angle of reflection | angle measured between the reflected ray and the normal line |
| reflection | bouncing light |
| refraction | bending light |
| density | how closely together particles are packed together |
| medium | a solid, liquid or gas |
| concave | a surface whose sides are pushed in toward the center |
| convex | a surface whose sides are pushed out from the center |
| hypothesis | an educated guess |
| absorb | soak in |
| transmit | allow something to pass through |
| infrared light | a wavelength longer than red - useful in many inventions |
