Waves (6091)+
Chapter 13: General Wave Properties
Types of Waves
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Longitudinal wave
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Transverse wave
Describe Waves
3D
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Measure wave
Side view
Measure Wave
frequency f: number of complete waves passing a point in one second
f =
speed v: distance moved by a wave in one second v = f λ
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Top view
Definition
Waves with vibrations perpendicular to the direction of travel of the waves Link
Demonstrate Transverse waves
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4
Longitudinal Wave
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Measuring LongitudinalWaves
Amplitude
Definition
Waves with vibrations parallel to the direction of travel of the waves. Link
Demonstrate Longitudinal waves Longitudinal waves
Longitudinal waves travels as a series of compressions and rarefactions. Longitudinal Wave
Wavelength
Frequency:
Speed
Longitudinal waves
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Example
Chapter 15: Sound wave Link ; Simulation 👍
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Properties
Speed
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Describing Sound
Sound caused by vibration.(measured in hertz, Hz)
Human can detect sound between 20 Hz - 20000 Hz
Above 20 000 Hz
Sonar: Determining the depth of objects.
Pitch: High frequency, high pitch; low frequency, low pitch
Loudness: Large amplitude, loud sound; small amplitude, soft sound
Sound wave can be reflected and refracted.
Reverberation
Speed depends of the type of medium it is travelling in.
Measure the speed of sound Link
Speed in solid, liquid and gas.
Reverberations are reflected sound that combine with the original sound, no distinct echos are heard.
Echolocation: Locating objects using echos.
period* T*: time for a particle on the wave to make one complete oscillation or time for one complete wave to go pass a point Period
wavelength λ: distance between two successive particles that are in phase
A displacement-time graph describes the displacement of one particle over a time interval.
Echo Link
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Refraction
Wave bends due to it changing speed
Deep to shallow water
Shallow to deep water
speed increases, wavelength increases, frequency unchanged
A displacement-distance graph allows the wavelength to be measured.
Ripple tank
Examples of transverse waves
Slinky
frequency f: number of complete waves passing a point in one second
f =
Sound travels as a series of compressions and rarefactions. Link
Waves transfer energy without transfering matter.
period
Transverse waves
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Chapter 14: Electromagnetic waves EM spectrum
Applications
They can travel through vacuum.
They transfer energy from one place to
another.
.
They all have a speed of
Rope Waves
No medium
Below 20 Hz
Electromagnetic waves
They obey the laws of reflection and refraction
speed v = frequency f x wavelength λ = f λ =
How sound is produced
Sound wave cannot travel through vacuum
Ultra violet
Visible light
X-ray
Infrared
Gamma rays
Microwaves
Radio waves
representing sound waves
Fastest in solid (densest material), slowest in gas (least dense)
speed decreases, wavelength decreases, frequency unchanged
Wave A Wave B
Wave A has a higher frequency than Wave B
v = fλ
period T = time for particle on the wave to make one oscillation
amplitude a: distance of crest to rest position
The tuning fork (vibrating object) causes the air layer in front of it to vibrate.
This in turn causes the next air layer to vibrate through the transfer of energy.
The continuous vibration creates a series of alternating compressions and rarefactions
and a longitudinal sound waves propagate outwards.
Water waves
Rope waves
Particles in the medium vibrate parallel to the direction of travel of the waves.
particles of medium
pressure in medium