Characteristics of WavesSection 2

Page 463-471

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Wave properties

Transverse waves have the shape of a sine curve

If they have the shape of a sine curve they are called sine waves

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Know these parts of a transverse wave

Crest—highest part of the wave

Trough—lowest part of the wave

Wavelength—the distance between two crests

Amplitude—the height of the wave

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Amplitude measures the amount of particle vibration

The greatest distance that a wave is displaced from its normal resting place

Also, half the distance from crest to trough

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99Amplitude is related to loudness!

http://sv.wikipedia.org/wiki/Bild:Amplitude_Wave.png

Wavelength

Measures the distance between two equivalent parts of the wave

Represented by the Greek letter lambda, λ

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Other important termsPeriod—how long it takes for waves to pass by Symbol is T SI Unit is seconds

Frequency –measures the rate of vibrations Symbol is f SI unit the hertz (Hz)

Frequency-Period Equation

Frequency = 1/period f=1/T 102

Radio Stations

Measure in

mHz—millions--FM

kHz—thousand—AM

95.1 T-95 classic rock, alternative

104.5 The FOX classic rock

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Electromagnetic Spectrum

Electromagnetic Spectrum

Radio—AM,FM, TV, radar aircraft navigation

Microwave—research and microwave ovens

Infrared—infrared photos, remote controls, heat radiation

Visible Light—ROYGBIV

UV light—sterilizing, fluorescent minerals, (sunburns)

X-ray—medical exams, cancer treatment

Gamma ray—food irradiation, studies of structural flaws 104

Radio waves have long wave lengths, so low frequency

Gamma rays have short wavelengths, so high frequency

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Visible light is only one small portion of the EM spectrum

Red has a long wave length

Violet has a short wavelength

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Speed of Sound340 m/sSound travels better in water

Sound travels even better in solids

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Speed of Light

3.00 x 108 m/s186,000 mi/s

Depends on the medium

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Pitch

Pitch is determined by

frequency High pitch = high

frequency Low pitch = low

frequency

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Doppler Effect

An observed change in the frequency of the wave when the source or observer is moving

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