click below
click below
Normal Size Small Size show me how
Physics
Physics - Semester 2 - Chapter 27 Key Terms
| Term | Definition |
|---|---|
| Electromagnetic spectrum | The range of electromagnetic waves extending from radio waves to gamma rays |
| Electromagnetic wave | A wave that is partly electric and partly magnetic and carries energy. Emitted by vibrating electric charges |
| Infrared | Electromagnetic waves of frequencies lower than the red of visible light |
| Light-year | The distance light travels through a vacuum during one year |
| Opaque | Term applied to materials that absorb light without reemission, and consequently do not allow light through them |
| Penumbra | A partial shadow that appears where light from part of the source is blocked and light from another part of the source is not blocked |
| Photon | In the particle model of electromagnetic radiation, a particle that travels only at the speed of light and whose energy is related to the radiation in the wave model |
| Polarization | The aligning of vibrations in a transverse wave, usually by filtering out waves of other directions |
| Ray | A thin beam of light |
| Shadow | A shaded region that results when light falls on an object and this cannot reach into the region on the far side of the object |
| Transparent | Term applied to materials that allow light to pass through them in straight lines |
| Ultraviolet | Electromagnetic waves of frequencies higher than those of violet light |
| Umbra | The darker part of a shadow where all the light is blocked |