Types of Waves With Respect
Transcript of Types of Waves With Respect
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WavesUnit 4
sound in air
AC electricity in a wire
• an earthquake in rock
• ocean waves in water
radio waves
light
infrared radiation
Xrays
gamma rays
• microwaves
• UV (ultraviolet)
Key Points:
1. Learn the characteristics of Transverse and
longitudinal Waves.
2. Understand how waves are created and
propagated.
3. Understand the properties of waves.
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Definion of A Wave• phenomenon by which energy propagates through a distance as a result of vibrational motions
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Types of Waves With Respect to Medium:
• Electromagnetic: these waves do not require a medium in which to travel. Light is an example of this. You will study these in Physics 30.
• Mechanical: these waves do require a medium in which to propagate.
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Types of Waves With Respect to Vibraonal Direcon :
• Longitudinal waves: the particles of the medium vibrate parallel to the direction of energy travel (cannot be polarized)
• Transverse waves: the particles of the medium vibrate perpendicularly to the direction of energy travel, (can be polarized)
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Diagram of a longitudinal wave:• particle displacement is parallel to the direction of wave propagation.
ENERGYWAVE
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Longitudinal Terminology:• Compression: is the region of higher concentration of the medium compared to the mean position.
• Rarefaction: is the region of lower concentration of the medium compared to the mean position.
Node: a stationary point in a vibratory body where the amplitude is zero.
*** Everything that can be said about a longitudinal wave can also be said about a transverse wave with polarization being the only exception.
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Longitudinal Waves
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Diagrams of Compression and Rarefacon
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Diagram of a Transverse Wave
• particle displacement is perpendicular to the direction of wave propagation.
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Labelled Transverse Wave
NodeEnergy
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Polarizaon of Transverse Wave
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Transverse Terminology:• Amplitude: the maximum displacement of the medium from the mean or zero position.
• Pulse: a single displacement of the medium
• Cycle: a repetition in the wave.
• Crest: the maximum positive displacement from the mean position
• Trough: the maximum negative displacement from the mean position. Opposite side of the crest.
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Other Terminology
• Node: A stationary point in a vibratory body where the amplitude is zero.
• The period and frequency of a wave are related by the equation
• Wavelength: it is the lateral displacement traveled during one cycle. (λ)
• Frequency: the number of cycles per unit time (Hz)
• Period: the time it takes to complete one cycle (s)
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Waves and SHMWaves are an example of SHM because they repeat over and over just like a mass on a spring or a pendulum. As shown below, a mass on a spring makes a sinusoidal wave pattern as it oscillates.
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The Wave Equaon• The universal wave equation links the velocity of a wave, the wavelength and the frequency of a wave in the following manner. Velocity depends upon the medium through which the wave is traveling.
• Velocity is constant for a given medium so:
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Examples:• Example 1 : A wave has a velocity of 70 .0 m/s and its frequency is 10.0 Hz. What is the wavelength?