Forces and Motion Essential Vocabulary 6.P.1.1 Compare the properties of waves to the wavelike property of energy in earthquakes, light and sound. 6.P.1.2 Explain the relationship among visible light, the electromagnetic spectrum, and sight. 6.P.1.3 Explain the relationship among the rate of vibration, the medium through which vibrations travel, sound and hearing.

Wave A moving disturbance that transfers energy through matter or space.

Transverse Waves A type of mechanical wave in which the wave energy causes matter in the medium to move up and down or back and forth at right angles to the direction the wave travels.

Longitudinal Waves A wave that causes the particles of the medium to vibrate parallel to the direction the wave travels.

Potential Energy Stored energy that results from the position or shape of an object.

Trough The lowest point of a transverse wave.

Crest The highest point of a transverse wave.

Time An interval separating two points of this quantity; a duration.

Period The time required for one full wavelength to pass a certain point.

Amplitude The distance from the crest (or trough) of a wave to the rest position of the medium.

Frequency The number of complete wavelengths that pass a point in a unit of time.

Wavelength The distance between a point on one wave and the identical point on the next wave.

Rarefaction The area of a longitudinal wave where the molecules are the most spread apart.

Reflection The bouncing back of a wave when it hits a surface or boundary.

Diffraction The bending of a wave as it passes an edge or an opening.

Interference The combination of two or more waves that exist in the same place at the same time.

Constructive Interference Any interference in which waves combine so that the resulting wave is bigger than the original waves.

Destructive Interference Any interference in which waves combine so the resulting wave is smaller than the largest of the original waves.

Compression The area of a longitudinal wave where the molecules are the most crowded together.

Seismic Waves Earthquake waves, including primary waves, secondary waves, and surface waves.

Electromagnetic Wave A wave caused by a disturbance in electric and magnetic fields. This sort of wave does not require a medium; also called a light wave.

EM Spectrum The range of all possible frequencies of electromagnetic radiation.

Visible Light Electromagnetic radiation that can be seen with the unaided eye.

Energy The ability to do work or cause change.

Sound Vibrations that travel through the air or another medium and can be heard when they reach a person's or animal's ear.

Vibration To move back and forth.

Medium The matter through which a wave travels.

Vacuum A place that is empty of all matter.

Pitch Perception of the frequency of a sound.

Hertz The unit of frequency; one hertz has a periodic interval of one second.

Speed/Wave Speed A measurement of how fast a wave passes through a medium.

Intensity The amount of energy per second carried through a unit area by a wave.

Decibel (dB) A unit used to compare the loudness of different sounds.

Amplification Increase the volume of; "amplify sound."

Acoustics The study of how sounds interact with each other and the environment.

Echolocation The use of reflected sound waves to determine distances or to locate objects.

Sonar A device that determines the distance of an object under water by recording echoes of sound waves.

Ultrasound Sound waves with frequencies above 20,000 Hz.

Doppler Effect An observed change in the frequency of a wave when the source or observer is moving.

Mechanical Wave A wave that requires a medium through which to travel.

RS A unit of radiation exposure.

Law of Resonance If an object vibrates at a certain rate of vibration, everything in its vicinity that has the same vibration as a dormant possibility will start vibrating at that frequency.

EM Wave Electromagnetic radiation (often abbreviated E-M radiation or EMR) is a phenomenon that takes the form of self-propagating waves in a vacuum or in matter.

Radio Waves A type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light. Like all other electromagnetic waves, they travel at the speed of light.

Microwaves A radio wave of very high frequency and short wavelength.

UV Light Electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays.

Infrared Light The wavelength of light produced above the visible part of the spectrum.

X-Rays Electromagnetic radiation of short wavelength produced when high-speed electrons strike a solid target.

Gamma Rays Penetrating electromagnetic radiation of shorter wavelength than X-rays.

Prism Optical device having a triangular shape and made of glass or quartz; used to deviate a beam or invert an image.

Primary Pigments Sets of colors that can be combined to make a useful range of colors.

Primary Colors Three colors that can be used to make any other color.

Optics The branch of physics that studies the physical properties of light.

Image A copy of an object formed by reflected or refracted rays of light.

Convex Curving or bulging outward.

Concave Curving inward.

Focal Point The point at which light rays parallel to the optical axis meet, or appear to meet, after being reflected (or refracted) by a mirror (or a lens).

Lens A curved piece of glass or other transparent material that is used to refract light.

Focal Length The distance between the center of a lens or curved mirror and its focus.

Cornea The transparent front surface of the eye.

Pupil The opening in the center of the iris through which light enters the inside of the eye.

Retina A layer at the back of the eyeball containing cells that are sensitive to light and that trigger nerve impulses that pass via the optic nerve to the brain, where a visual image is formed.

Optic Nerve Short, thick nerve that carries signals from the eye to the brain.

Cones Cells in the retina that respond to and detect color.

Rods Cells in the retina that detect dim light.

The End!!!