Exam 9: Resonance and Mechanical Waves

You are walking to an antique physics book sale with your friend and start talking about musical instruments. Your friend says that if we played violins and organs out in space, neither instrument could be heard because there would be nothing to oscillate any more, and no oscillation means no sound. Please comment on the physical accuracy of your friend's statement.

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Question 1

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Your friend must be careful. If they are saying that nothing will be able to oscillate your eardrums then they are correct because sound cannot travel through free space; it requires a medium. If they are talking about oscillations in the instruments, they are correct about the organ pipe but the guitar string will actually oscillate a little better due to the lack of air resistance.

Suppose you are a teacher and are trying to get the concept of interference across to your students. You are stuck at a stop light behind a car; both of you have your blinkers on and they blink with slightly different frequencies. Sometimes you notice they are on and off together and then a little later one is on while the other is off. Please explain how you could relate your traffic experience to a demonstration on wave interference.

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Question 2

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The blinkers being on could represent crests and their being off could represent wave troughs. When they are on together there is constructive interference and when one is off while the other is on they are in destructive interference.

The strings of a guitar vibrate at different frequencies. They have different thicknesses because

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Question 3

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You are at a coffee shop with a friend and have had enough caffeine that OSHA should be involved. You are talking late into the night with a friend who is a physics major and you say "I have absolutely no idea why pianos, guitars and xylophones all rely on transverse waves to make their sounds. I am going to re - construct those three instruments so they make beautiful music with longitudinal waves!" On the way home, the physics major thinks of a good reason that such instruments use only transverse waves. Please discuss what you think such a good reason may be.

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Question 4

Suppose a water wave strikes a very large solid barrier, such as a cliff. The wave will redirect its motion through

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Question 5

The waves produced by plucking a guitar string are

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Question 6

You are on your honeymoon but the only thing you can notice is that waves which strike the shore do so traveling directly towards it. This is an effect of

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Question 7

You bought a violin that was nicely tuned in the music store. When you took it home where the temperature is much different than the music store, the notes were not in tune any more. Please explain.

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Question 8

You just bought an old car which you want to restore. It still drives, though, so you decide to take some friends for a ride in it and you notice that, at stop lights the car bounces up and down because the shocks are gone. They're not bad; they're gone. Anyway, later that day you take many more friends in your car. At stop lights now, you notice that the bouncing frequency will

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Question 9

The Moon can create tides on the sides of the Earth closest to the Moon and farthest from it. This may seem peculiar, since there is nothing on the far side pulling the water up. Please explain.

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Question 10

You are holding a drinking straw in your hand so that both its ends are open to the air. When you blow air across one of those ends, the air in that straw vibrates and the straw emits a tone-its fundamental pitch. If you replace the air in the straw with carbon dioxide, which is more dense than air, the sound that the straw emits will

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Question 11

What does the period of a pendulum depend on?

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Question 12

The reason for using a harmonic oscillator as a clock's time-keeper is so that the clock will keep accurate time even if the

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Question 13

supplies part of the energy to a pendulum clock, while _ supplies most of the energy for a balance clock.

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Question 14

It is a windy day and there are waves on the surface of the open ocean. The wave crests are 40 feet apart and 5 feet above the troughs as they pass a school of fish. The waves push on fish and making them accelerate. The fish do not like this jostling, so to avoid it almost completely the fish should swim

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Question 15

Why does a tidal cycle take more than 12 hours?

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Question 16

Two tones which are one octave apart differ in frequency by a factor of

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Question 17

Many times in physics a typo can be embarrassing and costly. Consider the following typo sent to a press release by a clock designer that ended up costing them their job. "We have been successful in designing a balance clock with a anharmonic oscillator that gives high accuracy and low spring stress for increased clock life." Please explain why the designed lost their job.

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Question 18

For persons with hearing difficulties, it is sometimes recommended that they put their ear or even the area around their ear in contact with a table or solid surface in order to hear better. Please explain why doing such a thing could assist a person's hearing.

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Question 19

You decide to attend an amusement park which has a ride where you are strapped into a chair which is in turn firmly attached to a plastic cable. You are released and you bounce up and down as a harmonic oscillator-a mass on the end of spring. Next in line is somebody who weighs twice as much as you do. When the heavier person goes on the ride, you notice that

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Question 20

Showing 1 - 20 of 68

The strings of a guitar vibrate at different frequencies. They have different thicknesses because

Suppose a water wave strikes a very large solid barrier, such as a cliff. The wave will redirect its motion through

The waves produced by plucking a guitar string are

You are on your honeymoon but the only thing you can notice is that waves which strike the shore do so traveling directly towards it. This is an effect of

You bought a violin that was nicely tuned in the music store. When you took it home where the temperature is much different than the music store, the notes were not in tune any more. Please explain.

The Moon can create tides on the sides of the Earth closest to the Moon and farthest from it. This may seem peculiar, since there is nothing on the far side pulling the water up. Please explain.

What does the period of a pendulum depend on?

The reason for using a harmonic oscillator as a clock's time-keeper is so that the clock will keep accurate time even if the

supplies part of the energy to a pendulum clock, while _ supplies most of the energy for a balance clock.

Why does a tidal cycle take more than 12 hours?

Two tones which are one octave apart differ in frequency by a factor of

For persons with hearing difficulties, it is sometimes recommended that they put their ear or even the area around their ear in contact with a table or solid surface in order to hear better. Please explain why doing such a thing could assist a person's hearing.

The Laws of Motion, Part 1

The Laws of Motion, Part 2

Mechanical Objects, Part 1

Mechanical Objects, Part 2

Fluids

Fluids and Motion

Heat and Phase Transitions

Thermodynamics

Electricity

Magnetism and Electrodynamics

Electromagnetic Waves

Light

Optics and Electronics

Modern Physics

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Exam 9: Resonance and Mechanical Waves

The strings of a guitar vibrate at different frequencies. They have different thicknesses because

Suppose a water wave strikes a very large solid barrier, such as a cliff. The wave will redirect its motion through

The waves produced by plucking a guitar string are

You are on your honeymoon but the only thing you can notice is that waves which strike the shore do so traveling directly towards it. This is an effect of

You bought a violin that was nicely tuned in the music store. When you took it home where the temperature is much different than the music store, the notes were not in tune any more. Please explain.

The Moon can create tides on the sides of the Earth closest to the Moon and farthest from it. This may seem peculiar, since there is nothing on the far side pulling the water up. Please explain.

What does the period of a pendulum depend on?

The reason for using a harmonic oscillator as a clock's time-keeper is so that the clock will keep accurate time even if the

________ supplies part of the energy to a pendulum clock, while _________ supplies most of the energy for a balance clock.

Why does a tidal cycle take more than 12 hours?

Two tones which are one octave apart differ in frequency by a factor of

For persons with hearing difficulties, it is sometimes recommended that they put their ear or even the area around their ear in contact with a table or solid surface in order to hear better. Please explain why doing such a thing could assist a person's hearing.

The Laws of Motion, Part 1

The Laws of Motion, Part 2

Mechanical Objects, Part 1

Mechanical Objects, Part 2

Fluids

Fluids and Motion

Heat and Phase Transitions

Thermodynamics

Electricity

Magnetism and Electrodynamics

Electromagnetic Waves

Light

Optics and Electronics

Modern Physics

Filters

supplies part of the energy to a pendulum clock, while _ supplies most of the energy for a balance clock.