2.  A system of satellites, ground monitoring stations, and receivers that determine your exact location at or above Earth’s surface.  Global Positioning System (GPS)

3.  Radio waves with wavelengths of less than about 30 cm  microwaves

4.  Particle that electromagnetic waves sometimes behave like.  Photon

5.  Made by vibrating electric charges and can travel through space where matter is not present.  Electromagnetic Waves

6.  Low-frequency electromagnetic waves with wavelengths longer than about 1 mm.  Radio Waves

7.  Electromagnetic waves that have a wavelength between about 1mm and 750 billionths of a meter.  Infrared Waves

8.  Electromagnetic waves with wavelengths between about 400 billionths and 10 billionths of a meter.  Ultraviolet waves

9.  The specific frequency of the electromagnetic wave that a radio station is assigned.  Carrier Wave

10.  Electromagnetic wave with no mass and no charge that travels at the speed of light and is usually emitted with alpha or beta particles from a decaying atomic nucleus; has a wavelength less than about 10 trillionths.  Gamma ray

11.  The range of electromagnetic waves that you can detect with your eyes.  Visible Light

12.  The energy carried by an electromagnetic wave.  Radiant Energy

13.  A sealed vacuum tube in which one or more beams of electrons are produced.  Cathode-ray tube

14.  Transmits one radio signal and receives another signal from a base unit.  Transceiver

15.  Occurs when light traveling from one medium to another is completely reflected at the boundary between the two materials.  Total internal reflection

16.  Materials that allow some light to pass through them but you cannot see clearly through them.  Translucent

17.  Light from an ordinary light that can contain more than one wavelength, and its electromagnetic waves are not aligned.  Incoherent light

18.  An image of a distant object produced by the refraction of light through air layers of different densities.  Mirage

19.  Transmit almost all of the light striking them so you can see objects clearly through them.  Transparent

20.  Electromagnetic waves with wavelengths between about 10 billionths of a meter and 10 trillionths of a meter, that are often used for medical imaging.  X-rays

21.  Light that is generated by heating a piece of metal until it glows.  Incandescent light

22.  Uses phosphors to convert ultraviolet radiation to visible light.  Fluorescent light

23.  Light of only one wavelength that travels with its crests and troughs aligned.  Coherent light

24.  Light whose waves vibrate in only one direction.  Polarized light

25.  Only absorbs and reflects light- no light passes through it.  Opaque

26.  A technique that produces a hologram- a complete three dimensional photographic image of an object.  Holography

27.  A property of the material that indicates how much the speed of light in the material is reduced.  Index of refraction

28.  A colored material that is used to change the color of other substances.  Pigment