Types of WavesTypes of Waves

WavesWaves

Water wavesWater waves

Light wavesLight waves

Sound wavesSound waves

Seismic wavesSeismic waves

Wave nature of lightWave nature of light

Amplitude- The height of the wave.

Wave characteristics of lightWave characteristics of light

Frequency and wavelength are inversely relatedFrequency and wavelength are inversely related

c = λνc = λνOrOr

V=fλV=fλ

c or V= 3.0 x 10c or V= 3.0 x 1088 m/s m/sλ= wavelength (m)λ= wavelength (m)

v or f= frequency (Hertz= Hz)v or f= frequency (Hertz= Hz)

Types of WavesTypes of Waves

Longitudinal Wave (Compression)- Vibrates Longitudinal Wave (Compression)- Vibrates parallel (in the same direction) to the wave parallel (in the same direction) to the wave traveling.traveling.

Ex: Sound WavesEx: Sound Waves

Particles bump into each otherParticles bump into each other

Compression- Particles get closer together.Compression- Particles get closer together.

Rarefaction- Particles becoming thinner or more Rarefaction- Particles becoming thinner or more spread out.spread out.– The opposite of compressions.The opposite of compressions.

Transverse- Vibrate perpendicular (at right Transverse- Vibrate perpendicular (at right angles) to the wave traveling. angles) to the wave traveling. – Particles move up and down while wave Particles move up and down while wave

moves left to right. moves left to right.

Period- The time it takes for 1 full wave to Period- The time it takes for 1 full wave to pass. pass. – Period= 1 / Frequency Period= 1 / Frequency

Units: Seconds / WaveUnits: Seconds / Wave

Properties of WavesProperties of Waves

1) Reflection: Hitting a barrier.1) Reflection: Hitting a barrier.– RADAR- Send out EM waves and they RADAR- Send out EM waves and they

bounce back.bounce back.

2) Refraction: Bending a wave when the 2) Refraction: Bending a wave when the medium through which it travels changes.medium through which it travels changes.– Submarines use refraction in order not to be Submarines use refraction in order not to be

detected. detected.

3) Diffraction- Spreading of waves3) Diffraction- Spreading of waves– Bending waves around obstacles and Bending waves around obstacles and

openings.openings.Owls use this to communicate over long distancesOwls use this to communicate over long distances

4) Interference- Reinforcement or 4) Interference- Reinforcement or canceling of waves.canceling of waves.– Constructive Constructive – DestructiveDestructive

Doppler EffectDoppler Effect

http://science.discovery.com/videos/time-dopplerhttp://science.discovery.com/videos/time-doppler-effect.html-effect.html

An apparent shift in frequency for a sound wave An apparent shift in frequency for a sound wave produced by a moving source.produced by a moving source.– Shift in frequency + wavelength of waves which Shift in frequency + wavelength of waves which

results from a source moving with respect to the results from a source moving with respect to the medium. medium.

Works for all types of waves including light.Works for all types of waves including light.– Red shift - Occurs when the source + observer are Red shift - Occurs when the source + observer are

moving away from each other. moving away from each other. – Blue shift- Occurs when the source + observer are Blue shift- Occurs when the source + observer are

moving towards each other. moving towards each other.

Electromagnetic SpectrumElectromagnetic Spectrum

Visible LightVisible Light

Red – Longest wave, lowest energyRed – Longest wave, lowest energy

OrangeOrange

YellowYellow

GreenGreen

BlueBlue

IndigoIndigo

Violet – Shortest Wave, highest energyViolet – Shortest Wave, highest energy

Line SpectrumLine Spectrum

Seeing ColorSeeing Color

Retina- Made up of two types of cells that Retina- Made up of two types of cells that absorb light.absorb light.Cones- Distinguish colors and detailed Cones- Distinguish colors and detailed shapes; most effective in daytime vision.shapes; most effective in daytime vision.Rods- Sensitive to dim light; most effective Rods- Sensitive to dim light; most effective in nighttime vision.in nighttime vision.Color Blindness- Results when one or Color Blindness- Results when one or more sets of cones do not function more sets of cones do not function properly.properly.