Waves/Sound/Light/ Color Notes Conceptual Physics 5/26/2019

Wave – a rhythmic disturbance that carries energy through matter or space

Types of Waves Transverse Wave - a wave that vibrates perpendicular to the direction of the wave’s motion Longitudinal Wave - a wave that vibrates parallel to the direction of the wave’s motion 5/26/2019

Characteristics of Waves Crest - the high points of a wave Trough - the low points of a wave Amplitude(A) - the distance from the midpoint of a wave to its crest or trough 5/26/2019

More Characteristics of Waves Wavelength (λ) - the distance between two consecutive points on a wave (ex: crest to crest) Frequency (f) - the number of waves that pass a given point in one second, measured in Hertz(Hz) 5/26/2019

More Characteristics of Waves Rarefaction - part of a longitudinal wave where the molecules are spread farther apart Compression - part of a longitudinal wave where the molecules are closer together 5/26/2019

Speed of a wave : v=f λ (velocity= frequencyXwavelength) Interference of waves - when two or more waves combine they combine to form a new wave 5/26/2019

Types of Interference: Constructive Interference - when two or more waves combine to make a bigger wave than the original ones Destructive Interference - when two or more waves combine to make a smaller wave than the original ones 5/26/2019

Constructive Interference Destructive Interference

Standing Waves - waves that have stationary parts Nodes - points on a wave that do not move Antinodes - points on a wave that have the greatest amplitude (crests or troughs) 5/26/2019

Sound - longitudinal waves produced by the vibration of objects, the speed of sound depends on the elasticity of the medium it travels through and the temperature of the medium it travels through 5/26/2019

Sound (again) - the more elastic and warmer the medium the faster sound will travel, speed of sound in room temperature air is 340 m/s, sound travels faster in liquids than in gases and faster in solids than in liquids 5/26/2019

Light - an electromagnetic transverse wave that stimulates the retina of the eye; it travels in a straight line at 3X108 m/s; each color has a different wavelength with violet having the shortest wavelength and red having the longest; it can travel through space 5/26/2019

White - the reflection of all colors together Visible Spectrum - the part of light we can see; made of seven colors ROY G BIV (red, orange, yellow, green, blue, indigo, violet) White - the reflection of all colors together Black - absorption of all colors together 5/26/2019

Primary Colors of Light - red, green, blue (when you mix these you get white light) Primary Colors of Pigments(things that absorb certain colors and transmit others) - yellow, cyan, magenta (when you mix these colors you get black) 5/26/2019

Polarization - when light can only travel/vibrate in one direction Refraction - the bending of waves as they go from one medium to another Diffraction - the bending of waves around objects 5/26/2019

Reflection - when waves bounce back off an object a) regular reflection - when light bounces back in parallel beams as it off a mirror b) diffuse reflection - when light bounces back randomly and no image is formed as off a wall 5/26/2019

Mirrors - reflect light Law of Reflection - the angle of incidence equals the angle of reflection Lenses - refract light Mirrors - reflect light Prisms - separate light into the visible spectrum by refraction 5/26/2019

a)opaque - no light gets through Types of Objects: a)opaque - no light gets through b)translucent - some light gets through but no image c)transparent - all light gets through so an image is seen 5/26/2019