Vibration and Waves

Vibration and Standing Waves

By Stacy King

Standing waves can only be created when their motion is restricted to a given, finite region.​

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​Standing Wave

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​The waves do not appear to be moving

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​​Nodes

​points of no displacement

Antinodes​

points of maximum displacement​

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​Standing Wave

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Multiple Choice

Standing waves are created by

• Two identical waves reflecting off each other

• Two identical waves being diffracted together

• Two identical waves move through each other in opposite directions

• Two identical waves are diffracted from two identical sources

Multiple Choice

The moving black dot is called:

• a node
• an anti-node
• an anti-amplitude
• the wangy bit

Multiple Choice

The stationary dot is called:

• a node.
• an anti-node.
• the amplitude.
• the not moving bit.

Sound Waves

​Mechanical wave

• ​requires a medium

​Longitudinal wave

• compression and rarefaction

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Sound Waves

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Multiple Choice

A wave that requires a medium through which to travel

• mechanical wave
• chemical wave
• electromagnetic wave
• pitch

Multiple Choice

A disturbance that travels through a medium as a longitudinal wave

• sound
• wavelength
• pitch
• frequency

Pitch ​

​The sensation of frequency

Sound Waves

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Multiple Choice

How high or low a sound is; depends on the frequency (greater frequency= higher pitch)

• pitch
• frequency
• sound
• medium

Multiple Choice

Which of the following would you hear as a low pitched sound? 

• sound wave with a frequency of 50 Hz
• sound wave with frequency of 10,000 Hz
• sound wave with an intensity of 10 dB
• sound wave with an intensity of 100 dB

Intensity

The greater the amplitude

The greater the energy ​

Sound Waves

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Multiple Choice

Amplitude affects which characteristic of sound waves?

• frequency

• pitch

• loudness

• wave speed

​Speed of Sound in air

How fast the disturbance is passed from particle to particle​

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343 m / s​

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Sound Waves

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Multiple Choice

The speed of sound at standard temperature and pressure? (normal speed of sound through air)

• 331 m/s
• 365 m/s
• 621 m/s
• 343 m/s

Multiple Choice

Sound does not travel in space because

• Space is too far away.
• There is no matter in space.
• Space is the final frontier
• Space has planets.

Reflection of Sound Waves

echoes ​

• occur when a reflected sound wave reaches the ear more than 0.1 seconds after the original sound wave was heard​

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Sound Waves

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Multiple Choice

A reflected sound wave

• frequency
• pitch
• echo
• rarefaction

​Diffraction ​

​Sound waves are able to pass around barriers

Sound Waves

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Multiple Choice

Bending of waves around an object (such as through a doorway)

• sound
• diffract
• pitch
• volume

​Refraction ​

​Sound waves bend as the move through mediums with different densities.

Sound Waves

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Natural Frequency

​ is the frequency at which a system tends to oscillate in the absence of any driving or damping force

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Natural Frequency

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Multiple Choice

The number of cycles that are completed per second is called the ________ and is measured in _________.

• frequency, Hertz

• wavelength, meters

• amplitude, meters

• period, seconds

​ The actual frequency is determined by any factor that affects

• speed

• wavelength

frequency = speed/wavelength

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Natural Frequency

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Multiple Choice

A wave has a speed of 24 m/s and a wavelength of 0.04 m. What is the frequency of the wave?

• 600 Hz

• 600 m/s

• 0.096 Hz

• 0.04 Hz

Resonance

when one object vibrating at the same natural frequency of a second object forces that second object into vibrational motion​

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​Forced Vibration

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Multiple Choice

Motion when a varying force is used to drive an oscillating system

• Reverberation
• Over damping
• Forced oscillation
• Natural frequency

Multiple Choice

What occurs when vibrations traveling through an object match the object's natural frequency?

• reflection
• diffraction
• resonance
• refraction

Multiple Choice

When two objects vibrate at the same frequency it is called.....

• Diffraction
• Reflection
• Refraction
• Resonance