Waves - AP Physics 1
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At a local concert, a speaker is set up to produce low-pitched base sounds with a frequency range of 20Hz to 200Hz, which can be modeled as sine waves. In a simplified model, the sound waves the speaker produces can be modeled as a cylindrical pipe with one end closed that travel through the air at a velocity of 
, where T is the temperature in °C.
What type of waves are sound waves?
At a local concert, a speaker is set up to produce low-pitched base sounds with a frequency range of 20Hz to 200Hz, which can be modeled as sine waves. In a simplified model, the sound waves the speaker produces can be modeled as a cylindrical pipe with one end closed that travel through the air at a velocity of
What type of waves are sound waves?
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Sound waves are longitudinal waves, meaning that the waves propagate by compression and rarefaction of their medium. They are termed longitudinal waves because the particles in the medium through which the wave travels (air molecules in our case) oscillate parallel to the direction of motion. Alternatively, transverse waves oscillate perpendicular to the direction of motion. Common examples of transverse waves include light and, to a basic approximation, waves on the ocean.
Sound waves are longitudinal waves, meaning that the waves propagate by compression and rarefaction of their medium. They are termed longitudinal waves because the particles in the medium through which the wave travels (air molecules in our case) oscillate parallel to the direction of motion. Alternatively, transverse waves oscillate perpendicular to the direction of motion. Common examples of transverse waves include light and, to a basic approximation, waves on the ocean.
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All of the following are transverse waves, except .
All of the following are transverse waves, except .
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An important distinction for the MCAT is the difference between transverse and longitudinal waves. Although both wave types are sinusoidal, transverse waves oscillate perpendicular to the direction of propagation, while longitudinal waves oscillate parallel to the direction of propagation.
The most common transverse and longitudinal waves are light waves and sound waves, respectively. All electromagnetic waves (light waves, microwaves, X-rays, radio waves) are transverse. All sound waves are longitudinal.
An important distinction for the MCAT is the difference between transverse and longitudinal waves. Although both wave types are sinusoidal, transverse waves oscillate perpendicular to the direction of propagation, while longitudinal waves oscillate parallel to the direction of propagation.
The most common transverse and longitudinal waves are light waves and sound waves, respectively. All electromagnetic waves (light waves, microwaves, X-rays, radio waves) are transverse. All sound waves are longitudinal.
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Which of these is an example of a longitudinal wave?
Which of these is an example of a longitudinal wave?
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Longitudinal waves transmit energy by compressing and rarefacting the medium in the same direction as they are traveling. Sounds waves are longitudinal waves and travel by compressing the air through which they travel, causing vibration.
Light, X-rays, and microwaves are all examples of electromagnetic waves; even if you cannot recall if they are longitudinal or transverse, they are all members of the same phenomenon and will have the same type of wave transmission. Transverse waves are generated by oscillation within a plane perpendicular to the direction of motion. Oscillating a rope is a transverse wave, as it is not compressing in the direction of motion.
Longitudinal waves transmit energy by compressing and rarefacting the medium in the same direction as they are traveling. Sounds waves are longitudinal waves and travel by compressing the air through which they travel, causing vibration.
Light, X-rays, and microwaves are all examples of electromagnetic waves; even if you cannot recall if they are longitudinal or transverse, they are all members of the same phenomenon and will have the same type of wave transmission. Transverse waves are generated by oscillation within a plane perpendicular to the direction of motion. Oscillating a rope is a transverse wave, as it is not compressing in the direction of motion.
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Which of the following is not an example of a transverse wave?
Which of the following is not an example of a transverse wave?
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Transverse waves can be distinguished from longitudinal waves by the orientation of the oscillations to the direction of energy transfer. Transverse waves have oscillations perpendicular to the direction of energy transfer while longitudinal waves have oscillations parallel to the direction of energy transfer. The plucked guitar string may be tricky to think about because we use sound as a characteristic example of a longitudinal wave, and what does a plucked guitar string do but make sound? Well, the sound produced by the string is a longitudinal wave, but the string itself vibrates as a transverse wave. When the string is plucked, the energy is transferred down the string, yet the displacement is up and down or side to side. Meanwhile, an earthquake is a series of compressions that move underground due to shifting along a fault line for one. This is a longitudinal or compression wave. Another example of a transverse wave is those in the ocean. The wave oscillates vertically, causing rises and falls in the water level, but the waves are directed due offshore.
Transverse waves can be distinguished from longitudinal waves by the orientation of the oscillations to the direction of energy transfer. Transverse waves have oscillations perpendicular to the direction of energy transfer while longitudinal waves have oscillations parallel to the direction of energy transfer. The plucked guitar string may be tricky to think about because we use sound as a characteristic example of a longitudinal wave, and what does a plucked guitar string do but make sound? Well, the sound produced by the string is a longitudinal wave, but the string itself vibrates as a transverse wave. When the string is plucked, the energy is transferred down the string, yet the displacement is up and down or side to side. Meanwhile, an earthquake is a series of compressions that move underground due to shifting along a fault line for one. This is a longitudinal or compression wave. Another example of a transverse wave is those in the ocean. The wave oscillates vertically, causing rises and falls in the water level, but the waves are directed due offshore.
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Which of these is an example of a longitudinal wave?
Which of these is an example of a longitudinal wave?
Tap to reveal answer
Longitudinal waves transmit energy by compressing and rarefacting the medium in the same direction as they are traveling. Sounds waves are longitudinal waves and travel by compressing the air through which they travel, causing vibration.
Light, X-rays, and microwaves are all examples of electromagnetic waves; even if you cannot recall if they are longitudinal or transverse, they are all members of the same phenomenon and will have the same type of wave transmission. Transverse waves are generated by oscillation within a plane perpendicular to the direction of motion. Oscillating a rope is a transverse wave, as it is not compressing in the direction of motion.
Longitudinal waves transmit energy by compressing and rarefacting the medium in the same direction as they are traveling. Sounds waves are longitudinal waves and travel by compressing the air through which they travel, causing vibration.
Light, X-rays, and microwaves are all examples of electromagnetic waves; even if you cannot recall if they are longitudinal or transverse, they are all members of the same phenomenon and will have the same type of wave transmission. Transverse waves are generated by oscillation within a plane perpendicular to the direction of motion. Oscillating a rope is a transverse wave, as it is not compressing in the direction of motion.
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At a local concert, a speaker is set up to produce low-pitched base sounds with a frequency range of 20Hz to 200Hz, which can be modeled as sine waves. In a simplified model, the sound waves the speaker produces can be modeled as a cylindrical pipe with one end closed that travel through the air at a velocity of , where T is the temperature in °C.
What type of waves are sound waves?
At a local concert, a speaker is set up to produce low-pitched base sounds with a frequency range of 20Hz to 200Hz, which can be modeled as sine waves. In a simplified model, the sound waves the speaker produces can be modeled as a cylindrical pipe with one end closed that travel through the air at a velocity of
What type of waves are sound waves?
Tap to reveal answer
Sound waves are longitudinal waves, meaning that the waves propagate by compression and rarefaction of their medium. They are termed longitudinal waves because the particles in the medium through which the wave travels (air molecules in our case) oscillate parallel to the direction of motion. Alternatively, transverse waves oscillate perpendicular to the direction of motion. Common examples of transverse waves include light and, to a basic approximation, waves on the ocean.
Sound waves are longitudinal waves, meaning that the waves propagate by compression and rarefaction of their medium. They are termed longitudinal waves because the particles in the medium through which the wave travels (air molecules in our case) oscillate parallel to the direction of motion. Alternatively, transverse waves oscillate perpendicular to the direction of motion. Common examples of transverse waves include light and, to a basic approximation, waves on the ocean.
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All of the following are transverse waves, except .
All of the following are transverse waves, except .
Tap to reveal answer
An important distinction for the MCAT is the difference between transverse and longitudinal waves. Although both wave types are sinusoidal, transverse waves oscillate perpendicular to the direction of propagation, while longitudinal waves oscillate parallel to the direction of propagation.
The most common transverse and longitudinal waves are light waves and sound waves, respectively. All electromagnetic waves (light waves, microwaves, X-rays, radio waves) are transverse. All sound waves are longitudinal.
An important distinction for the MCAT is the difference between transverse and longitudinal waves. Although both wave types are sinusoidal, transverse waves oscillate perpendicular to the direction of propagation, while longitudinal waves oscillate parallel to the direction of propagation.
The most common transverse and longitudinal waves are light waves and sound waves, respectively. All electromagnetic waves (light waves, microwaves, X-rays, radio waves) are transverse. All sound waves are longitudinal.
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Which of the following is not an example of a transverse wave?
Which of the following is not an example of a transverse wave?
Tap to reveal answer
Transverse waves can be distinguished from longitudinal waves by the orientation of the oscillations to the direction of energy transfer. Transverse waves have oscillations perpendicular to the direction of energy transfer while longitudinal waves have oscillations parallel to the direction of energy transfer. The plucked guitar string may be tricky to think about because we use sound as a characteristic example of a longitudinal wave, and what does a plucked guitar string do but make sound? Well, the sound produced by the string is a longitudinal wave, but the string itself vibrates as a transverse wave. When the string is plucked, the energy is transferred down the string, yet the displacement is up and down or side to side. Meanwhile, an earthquake is a series of compressions that move underground due to shifting along a fault line for one. This is a longitudinal or compression wave. Another example of a transverse wave is those in the ocean. The wave oscillates vertically, causing rises and falls in the water level, but the waves are directed due offshore.
Transverse waves can be distinguished from longitudinal waves by the orientation of the oscillations to the direction of energy transfer. Transverse waves have oscillations perpendicular to the direction of energy transfer while longitudinal waves have oscillations parallel to the direction of energy transfer. The plucked guitar string may be tricky to think about because we use sound as a characteristic example of a longitudinal wave, and what does a plucked guitar string do but make sound? Well, the sound produced by the string is a longitudinal wave, but the string itself vibrates as a transverse wave. When the string is plucked, the energy is transferred down the string, yet the displacement is up and down or side to side. Meanwhile, an earthquake is a series of compressions that move underground due to shifting along a fault line for one. This is a longitudinal or compression wave. Another example of a transverse wave is those in the ocean. The wave oscillates vertically, causing rises and falls in the water level, but the waves are directed due offshore.
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A student at a concert notices that a balloon near the large speakers moving slightly towards, then away from the speaker during the low-frequency passages. The student explains this phenomenon by noting that the waves of sound in air are waves.
A student at a concert notices that a balloon near the large speakers moving slightly towards, then away from the speaker during the low-frequency passages. The student explains this phenomenon by noting that the waves of sound in air are waves.
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Sound is a longitudinal, or compression wave. A region of slightly more compressed air is followed by a region of slightly less compressed air (called a rarefaction). When the compressed air is behind the balloon, it pushes it forward, and when it is in front of the balloon, it pushes it back. This only works if the frequency is low, because the waves are long enough so that the balloon can react to them.
Sound is a longitudinal, or compression wave. A region of slightly more compressed air is followed by a region of slightly less compressed air (called a rarefaction). When the compressed air is behind the balloon, it pushes it forward, and when it is in front of the balloon, it pushes it back. This only works if the frequency is low, because the waves are long enough so that the balloon can react to them.
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A guitar player uses beats to tune his instrument by playing two strings. If one vibrates at 550 Hz and the second at 555 Hz, how many beats will he hear per minute?
A guitar player uses beats to tune his instrument by playing two strings. If one vibrates at 550 Hz and the second at 555 Hz, how many beats will he hear per minute?
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Two waves will emit a beat with a fequency equal to the difference in frequency of the two waves. In this case the beat frequency is:
(beats per second)
Convert to beats per minute:
Two waves will emit a beat with a fequency equal to the difference in frequency of the two waves. In this case the beat frequency is:
Convert to beats per minute:
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Alice measures the wavelength and frequency of a sound wave as
At what speed is the sound traveling?
Alice measures the wavelength and frequency of a sound wave as
At what speed is the sound traveling?
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We know from the question that
Frequency is the inverse of period:
The velocity of a wave is its wavelength multiplied by its frequency:
We know from the question that
Frequency is the inverse of period:
The velocity of a wave is its wavelength multiplied by its frequency:
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You are standing on the sidewalk when a police car approaches you at 
with its sirens on. Its sirens seem to have a frequency of 500 Hertz. After the police car passes you and is driving away, what will be the new frequency you hear?
You are standing on the sidewalk when a police car approaches you at
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The doppler effect follows this formula:
In this equation, 
is the new frequency you will hear, 
is the speed of sound, 
is the velocity of the moving sound-emitting thing, and 
is the initial frequency of the sound.
Plugging the given values in, we can describe the initial situation as:
Note that the velocity is negative 
because the car is driving towards you.
Therefore,
When the police car is driving away, the situation is described with a positive velocity:
Therefore,
The doppler effect follows this formula:
In this equation,
Plugging the given values in, we can describe the initial situation as:
Note that the velocity is negative
Therefore,
When the police car is driving away, the situation is described with a positive velocity:
Therefore,
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The ukulele is a short instrument, relative to a guitar. How does this affect the frequencies of sounds that these two instruments produce? Assume the two instruments use the same strings.
The ukulele is a short instrument, relative to a guitar. How does this affect the frequencies of sounds that these two instruments produce? Assume the two instruments use the same strings.
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The speed of sound in air is constant, assuming that the temperature of the air is constant. When the length of the string is shortened, by the principles of standing waves, this creates a higher frequencies. Assuming that the two instruments use the same strings is equivalent to stating that the two instruments have strings of equal linear mass density. This situation represents a standing wave, thus we can relate the following equation for the first harmonic:
Where, 
is the length of the string and 
is the wavelength. Then we can use the following equation to relate wavelength and speed (which is known) to frequency:
Since the velocity of sound in a fixed medium is constant, we see that a shorter length, 
corresponds to a shorter wavelength, 
. Thus when 
decreases, frequency, 
must increase, to keep velocity constant.
The speed of sound in air is constant, assuming that the temperature of the air is constant. When the length of the string is shortened, by the principles of standing waves, this creates a higher frequencies. Assuming that the two instruments use the same strings is equivalent to stating that the two instruments have strings of equal linear mass density. This situation represents a standing wave, thus we can relate the following equation for the first harmonic:
Where,
Since the velocity of sound in a fixed medium is constant, we see that a shorter length,
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A sound played from a speaker is heard at an intensity of 100W from a distance of 5m. When the distance from the speaker is doubled, what intensity sound will be heard?
A sound played from a speaker is heard at an intensity of 100W from a distance of 5m. When the distance from the speaker is doubled, what intensity sound will be heard?
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Intensity is related to radius by the inverse square law:
This equation is derived from the concept that the energy from the sound waves is conserved and spread out over an area, producing the 
term. Applying this concept, when the radius doubles, the intensity decreases by a factor of 4. The correct answer is 
.
Intensity is related to radius by the inverse square law:
This equation is derived from the concept that the energy from the sound waves is conserved and spread out over an area, producing the
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A stopped pipe (closed at both ends) sounds a frequency of 500Hz at its fundamental frequency. What is the length of the pipe?
A stopped pipe (closed at both ends) sounds a frequency of 500Hz at its fundamental frequency. What is the length of the pipe?
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A stopped pipe can be modeled with the following equation:
Rearrange the equation to solve for L, then plug in given values and solve.
Rearrange the equation to solve for L, then plug in given values and solve.
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What is the beat frequency between a 305Hz and a 307Hz sound?
What is the beat frequency between a 305Hz and a 307Hz sound?
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Frequency of beats is determined by the absolute value of the difference between two different frequencies. Thus, the beats frequency is 2Hz. Note that beat frequency is always a positive number.
Frequency of beats is determined by the absolute value of the difference between two different frequencies. Thus, the beats frequency is 2Hz. Note that beat frequency is always a positive number.
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An open pipe (open at both ends) has a fundamental frequency of 600Hz. How long is the pipe?
An open pipe (open at both ends) has a fundamental frequency of 600Hz. How long is the pipe?
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An open pipe can be modeled by the following equation:
Rearrange the equation to solve for 
then plug in given values and solve.
An open pipe can be modeled by the following equation:
Rearrange the equation to solve for
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Consider a 37cm long harp string with a fundamental frequency of 440Hz.
Calculate the speed of the standing wave created by plucking this string.
Consider a 37cm long harp string with a fundamental frequency of 440Hz.
Calculate the speed of the standing wave created by plucking this string.
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Use the following equation to find the velocity of the wave, using its fundamental frequency and the length:
Use the following equation to find the velocity of the wave, using its fundamental frequency and the length:
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Consider a 37cm long harp string with a fundamental frequency of 440Hz.
Suppose the string is pressed down in such a way that only a 10cm length of string vibrates. What is the speed of the wave produced when the string is plucked in terms of 
the speed of the wave when all 37cm of the string vibrate?
Consider a 37cm long harp string with a fundamental frequency of 440Hz.
Suppose the string is pressed down in such a way that only a 10cm length of string vibrates. What is the speed of the wave produced when the string is plucked in terms of
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The speed of a wave is a property of the medium, it is not affected by the length of the string. The frequency may change, but the speed remains constant. There is no change in the speed.
The speed of a wave is a property of the medium, it is not affected by the length of the string. The frequency may change, but the speed remains constant. There is no change in the speed.
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Consider a 37cm long harp string with a fundamental frequency of 440Hz.
If only half of the string is allowed to vibrate, what frequency will be heard?
Consider a 37cm long harp string with a fundamental frequency of 440Hz.
If only half of the string is allowed to vibrate, what frequency will be heard?
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Since the speed of the wave does not change based on the length of the string and we know it has a fundamental frequency of 440Hz, a string of half the length will vibrate at twice the frequency, 880Hz. This makes sense as it will sound higher in pitch. You can try this with a rubber band on a shoebox. Plucking it while placing your finger halfway along the band will result in a higher pitched sound.
Since the speed of the wave does not change based on the length of the string and we know it has a fundamental frequency of 440Hz, a string of half the length will vibrate at twice the frequency, 880Hz. This makes sense as it will sound higher in pitch. You can try this with a rubber band on a shoebox. Plucking it while placing your finger halfway along the band will result in a higher pitched sound.
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