Properties of Waves Interactions Wave Properties l There

Properties of Waves & Interactions

Wave Properties l There are 4 properties of wave l Amplitude l Wavelength l Frequency l Wave speed

Wave Properties l Amplitude l The maximum distance that the particles of a wave vibrate from the rest position. l An other words from the rest position to the crest or from the rest position to the trough.

Wave Properties l Amplitude l Shows the amount of energy there is in a wave. l The bigger the amplitude the more energy there is.

Wave Properties l Wavelength l The distance from any point on a wave to an identical point on the next wave. l Generally measured from crest to crest on a transverse wave and from compression to compression on a longitudinal wave.

Wave Properties l Wavelength l The shorter the wavelength the more energy there is.

Wave Properties l Frequency l The number of waves produced in a given amount of time l Measured in Hertz (Hz) l 1 Hz=1/s (1 wave per second)

Wave Properties l Frequency l The higher the frequency the more energy

Wave Properties l Wave Speed l The speed at which a wave travels l V= λ x f v – wave speed λ – wavelength f – frequency l The wavelength and frequency of a wave in a certain medium depends on the wave speed not the other way around § http: //micro. magnet. fsu. edu/primer/java/wavebasics/index. html

Wave Interactions l There are 4 types of wave interactions l Reflection l Refraction l Diffraction l Interference

Wave Interactions Reflection l l The bouncing back of a wave when it hits a surface. * NOTE: When waves hits a substance some of it is transmitted and some of it is reflected. Transmitted means to pass through l This is why we can see objects and hear echoes.

Wave Interactions Refraction l The bending of waves as they pass through different mediums that cause the speed of the wave to change. l § Prism

Wave Interactions l Diffraction l Change of direction of a wave when it hits an obstacle or edge. § Sound diffracts well around corners § Light does not diffract as much because their wavelengths are shorter

Wave Interactions Interference l When 2 or more waves combine l l l Two objects can’t occupy the same space at the same time, but waves can. There are 4 types of interference l Constructive interference l Destructive interference l Standing waves l Resonance

Interference Constructive interference l l When the crest and trough of different waves match l They combine to make a wave with larger amplitude

Interference Destructive interference l l When the crest of one wave meets the trough of another l The results are a smaller amplitude or no amplitude

Interference Standing waves l l When waves combined they look like they are standing still, but are not. l It is a combination of constructive and destructive interference

Interference Resonance l l When 2 objects naturally vibrate at the same frequency. l The sound produced by one object causes the other to vibrate. l Body of a guitar resonates when the strings are strummed

Bibliography l l Holt, Rinehart, Winston, North Carolina Holt Science & Technology, Holt, Rinehart, Winston, Orlando, 2005 Google Images, http: //www. google. com/imghp, accessed 1/12/11