5 Where Do Waves Get Energy? Vibration - movement that follows the same path repeatedlyAn object that is vibrating is moving, and if it is moving it has energy.The movement of energy from a vibrating source outward is a wave.
6 The matter, or substance, through which a wave is transmitted is called a medium. Water is a medium for ocean waves.Air is a medium for sound waves.
7 Types of WavesMechanical Waves - require a medium!a. Transverse b. Compressional orLongitudinal2. Electromagnetic Waves - can travel through matter and empty space.
8 CLICK the Slinky to watch a transverse wave. causes particles in matter to move back and forth at right angles to the direction in which the wave travelsCLICK the Slinky to watch a transverse wave.
9 ·high points are called crests ·low points are called troughs Please draw a picture of this in your notes. Label the crests and trough.
10 Longitudinal or Compressional Wave causes particles in matter to move back and forth along the same direction in which it travels
11 CLICK below to watch a compressional wave. RAREFACTIONCOMPRESSIONDRAW & LABEL IN NOTESCompressions - coils are squeezed togetherRarefactions - coils are spread apart
12 Surface WavesWave that consists of a combination of transverse and longitudinal waves and occurs at the surface between two different mediumsSurface waves occur at thesurface between two differentmediums – water and air.
13 Electromagnetic Waves transverse wave that contain electric and magnetic parts that vibrate perpendicular to the direction that the wave travels
14 Properties of WavesWavelength - distance between one point on a wave and the nearest point just like it
15 Frequency - number of full wavelengths that pass by a point each second *The unit used to measure wave frequency is called the hertz(Hz)*One hertz is equal to one wave, or cycle, per second:1 Hz = 1 wave/sec.
16 Amplitude - half the distance between a crest and trough
17 Wave Speed - distance per time that a given wave travels. Waves travel at different speeds in different mediumsSpeed =Frequency X Wavelength