a disturbance that transfers energy Carries energy from one place to another Classified by what they move through

WAVES

WAVES a disturbance that transfers energy Carries energy from one place to another Classified by what they move through 1. Mechanical Waves the energy is transferred by vibrations of medium (medium = matter, stuff) ex/ ocean waves move through water 2. Electromagnetic waves (EM Waves) the energy moves through disturbances in the electromagnetic field.

WAVE STRUCTURE CREST (peak) AMPLITUDE middle to max peak WAVELENGTH TROUGH

WAVE STRUCTURE Wavelength the distance between the same point in two waves. Amplitude the distance from the middle of the wave to the maximum crest or trough. Frequency The number of waves that pass a specific point each second.

MECHANICAL WAVES require a medium (the material through which the wave is moving) to transmit energy travel through & gradually lose energy to that medium Examples: water, sound, rope, & spring waves Mechanical Media: water, air, rope, spring Making a pulse

MECHANICAL WAVES 3 types: transverse Longitudinal surface

TRANVERSE WAVES Vibration is perpendicular to the direction of the motion of the wave Sideways or up & down Examples: S-type earthquake waves Electromagnetic waves (ex: light)

LONGITUDINAL WAVES Vibration is parallel to the direction of the motion of the wave Back and forth (compression & rarefraction) Also called compression or pressure wave Examples: P-type earthquake waves Sound waves Rarefraction (expansion) Compression

SURFACE WAVES Vibration is circular Occur at the boundary between two different mediums Particles move more the closer they are to the surface Example: Ocean waves

CHARACTERISTICS OF WAVES Amplitude the distance from the middle of the wave to the maximum peak. Frequency ƒ the number of waves that pass a specific point each second. Wavelength the distance between the same point in two waves. Velocity v speed = how fast the wave travels v = ƒ

AMPLITUDE Distance between the middle & crest or middle & trough Gives indication of the power of a wave Does not affect the velocity of a wave Determines strength (earthquake), loudness (sound), or brightness (electromagnetic wave)

WAVELENGTH Distance between any two repeating points on a wave crest-crest, trough-trough, expansion-expansion, compression-compression Determines what colors we see; what notes we hear (pitch) Shorter wavelengths have a higher frequency because the waves aren t as long

measured in wavelengths/second Hertz (Hz) = number of wavelengths in 1 second Frequency ƒ the number of waves that pass a specific point each second.

VELOCITY v the rate at which the wave travels Depends on medium Mechanical waves travel faster through dense mediums EM Waves are faster through less dense mediums

Which is a longitudinal wave, and which is a transverse wave?

Earthquakes Waves traveling through the ground.

Wave diffraction A change in the direction of a wave as they pass through an opening or around an object in their path

Waves can be absorbed by objects and converted into other types of energy. Light waves can be absorbed by objects and in most cases the energy is converted into heat.

Wave interference. Two waves can interact with one another, this interaction is called interference. Constructive Destructive