Wave Properties & Interactions

Wave Properties There are 5 properties of a wave Amplitude Wavelength Frequency Wave speed Period

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

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

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

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

Wave Properties Frequency The number of wavelengths that pass by a point each second. Measured in Hertz (Hz) 1Hz=1/s (1 wave per second) The higher the frequency the more energy

Wave Properties Wave Speed The speed at which a wave travels Wave Speed (m/s) = Frequency (Hz) x Wavelength (m) S= λ x f S – wave speed λ – wavelength f – frequency

Wave Period The wave period is the measure of time it takes for the wave cycle to complete. We usually measure the wave period in seconds and represent it with the letter T. Let's say we determine a wave moves at 60 Hertz; that wave will have 60 cycles per second. When writing formulas, Hertz is usually abbreviated to Hz. https://www.youtube.com/watch?v=v3CvAW8BDHI

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

Wave Interactions Reflection 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 This is why we can see objects and hear echoes.

Wave Interactions The Law of Reflection states When a wave is reflected from a surface, the angle of reflection is equal to the angle of incidence.

Wave Interactions Refraction The bending of waves as they pass through different mediums that cause the speed of the wave to change. Light bending when in air and liquid https://www.youtube.com/watch?v=JRh0CGfX7dQ https://www.youtube.com/watch?v=k0eGjaEWpPU

Wave Interactions Diffraction: Change in 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 https://www.youtube.com/watch?v=wlcsSdsJG6I

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

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

Interference Destructive interference When the crest of one wave meets the trough of another The results are a smaller amplitude or no amplitude https://www.youtube.com/watch?v=eW5VGGJuWtQ

Interference Standing waves When waves combined they look like they are standing still, but are not. It is a combination of constructive and destructive interference https://www.youtube.com/watch?v=jz8IIk_bps0&t=298s

Interference Resonance When 2 objects naturally vibrate at the same frequency. The sound produced by one object causes the other to vibrate. https://www.youtube.com/watch?v=dihQuwrf9yQ Body of a guitar resonates when the strings are strummed