Constructive Interference – Result is a larger amplitude When Two Waves Meet…  Destructive Interference – Result is a smaller amplitude  Waves pass through.

Slides:



Advertisements
Similar presentations
A disturbance in a medium that transfers energy and momentum
Advertisements

Beats and Resonance Sections 9.3 and 9.4.
Unit: Oscillations and Waves I.Oscillatory Motion: Amplitude, Frequency, and Velocity a)Mass on a spring b)Pendulums II.Traveling Waves a)Types and properties.
SOUND WAVES Sound is a longitudinal wave produced by a vibration that travels away from the source through solids, liquids, or gases, but not through a.
Beats  Different waves usually don’t have the same frequency. The frequencies may be much different or only slightly different.  If the frequencies are.
Cutnell/Johnson Physics 8th edition Reading Quiz Questions
Doppler Effect Physics 202 Professor Lee Carkner Lecture 11.
Test Physics 202 Professor Lee Carkner Lecture 10.
Sound Waves - Beats Wei-En Hsu Center for Advanced Computation and Telecommunications UMass Lowell.
Doppler Effect Physics 202 Professor Lee Carkner Lecture 11.
SOUND UNIT NOTES. The Nature of Sound Sound is a disturbance that travels through a medium as a longitudinal wave.
Waves and Sound Ch
Six Flags registration due next Friday!!!!!!
THE PHYSICS OF MUSIC ♫. MUSIC Musical Tone- Pleasing sounds that have periodic wave patterns. Quality of sound- distinguishes identical notes from different.
L 23 – Vibrations and Waves [3] resonance  clocks – pendulum  springs  harmonic motion  mechanical waves  sound waves  golden rule for waves Wave.
L 22 – Vibrations and Waves [3] resonance  clocks – pendulum  springs  harmonic motion  mechanical waves  sound waves  golden rule for waves Wave.
2.4 Addition of waves Simulation bcs/Books?action=mininav&bcsId=4768&itemId= &assetId =160342&resourceId=15301&newwindow=true.
The Principle of Linear Superposition and Interference Phenomena CHAPTER 17 Interference Constructive and Destructive Interference: BEATS Standing Waves:
Explain what beats are and why they occur… 1)When two sounds are slightly different in frequency, a “warbling” beat is heard 2)This is because the two.
AGENDA Chapter 13 Notes Chapter 13 Notes United Streaming Video on Sound United Streaming Video on Sound.
L 23 – Vibrations and Waves [3]  resonance   clocks – pendulum   springs   harmonic motion   mechanical waves   sound waves  golden rule for.
Diffraction What happens when a wave encounters an obstacle or opening? It ``bends’’ around it. Consider a wave front (a wave in 2D) viewed from above.
L 23 – Vibrations and Waves [3]  resonance  clocks – pendulum  springs  harmonic motion  mechanical waves  sound waves  golden rule for waves 
Anything that vibrates generates a sound! (unless it’s in a vacuum)
ALL sounds are produced by vibrations. Sound waves travel as longitudinal (compressional) waves. Compression – region of high molecular density and.
Sound Waves Sound waves are divided into three categories that cover different frequency ranges Audible waves lie within the range of sensitivity of the.
Like all waves, sound waves are produced by a vibration.  A tuning fork vibrates to produce a sound.  A guitar string vibrates to produce a sound.
Sound quality and instruments  Different notes correspond to different frequencies  The equally tempered scaled is set up off of 440 A  meaning the.
A “physical phenomenon that stimulates the sense of hearing.”
Stringed Instruments (Ex. Guitars, pianos, violins)  Vibrating the string sets up a standing wave, the vibration from the string resonate the sounding.
L 23 – Vibrations and Waves [3]  resonance   clocks – pendulum   springs   harmonic motion   mechanical waves   sound waves  golden rule for.
What about the rubber bands determines pitch? Musical Instruments - Strings  The pitch or frequency of a string is determined by the string’s velocity.
Chapter 14 Sound. Sound waves Sound – longitudinal waves in a substance (air, water, metal, etc.) with frequencies detectable by human ears (between ~
Superposition of waves Standing waves on a string Interference Lecture 27: Wave interference.
Physics 6B Waves and Sound Examples Prepared by Vince Zaccone For Campus Learning Assistance Services at UCSB.
Sound and the Doppler Effect. Sound is a Mechanical Wave What is a mechanical wave? A mechanical wave is any wave that needs a medium.
Sound Waves You Have to Hear This!!!! Producing a Sound Wave Like all waves, sound waves are produced by a ________.  A tuning fork ________ to produce.
L 23 – Vibrations and Waves [3]  resonance   clocks – pendulum   springs   harmonic motion   mechanical waves   sound waves  golden rule for.
Sect. 12-6: Sound Wave Interference & Beats Like any other waves, sound waves can interfere with each other. Example Can lead to beats.
Chapter 26 Sound. Sound is a form of energy that spreads out through space.
14-6 The Doppler Effect The Doppler effect is the change in pitch of a sound when the source and observer are moving with respect to each other. When an.
Pipe Instruments (Ex. Flutes, trumpets, pipe organs)
L 22 – Vibrations and Waves [3]
L 23 – Vibrations and Waves [3]  resonance   clocks – pendulum   springs   harmonic motion   mechanical waves   sound waves  golden rule for.
If two sounds are only slightly off in terms of frequency The ‘Beats’  Produce a periodic rise and fall of amplitude (volume)  Throbbing Sound = Beats.
Moving Source Going Faster Moving at the Speed of Sound Moving Faster than Sound Supersonic Mach I Pressure wave, piled up at nose Shock wave of constructive.
1 L 23 – Vibrations and Waves [3]  resonance  clocks – pendulum  springs  harmonic motion  mechanical waves  sound waves  golden rule for waves.
The Principle of Linear Superposition and Interference Phenomena CHAPTER 17 Interference Constructive and Destructive Interference: BEATS Standing Waves:
15.1 Properties and Detection of Sound Interference of sound waves.
Chapter 17 Sound Wave Hearing is one of our most important senses.
Today (Finish Chapter 13, Sound)  Temperature and Heat Concepts Tomorrow (Start Chapter 14)  Standing Waves  Beats  Doppler Effect  Example Problems.
Sound Part II  Music What is the study of sound called?  Acoustics.
L 23 – Vibrations and Waves [3]  resonance   clocks – pendulum   springs   harmonic motion   mechanical waves   sound waves  golden rule for.
~ Sound ~ The Nature of Sound  Speed of Sound  Human hearing  Doppler effect  “Seeing” with sound.
Interference and beats Pg. 47. Objectives Investigate and analyze characteristics of waves, including frequency and amplitude. Investigate and analyze.
Chapter 18 Waves and Sound
Waves 1 The Transfer of Energy. The Basics: A λ d(m) (#λ or m) d = displacement Amplitude = max displacement from origin λ = wavelength (in m) f = frequency.
L 22 – Vibrations and Waves [3]
Warm-Up: Doppler Effect #1
Musical Instruments.
Mechanical Wave Interactions
Waves 1 The Transfer of Energy.
L 23 – Vibrations and Waves [3]
Wave interference and Beat Frequency
Chapter 13 Objectives Explain why resonance occurs.
1. Which of the following is a false statement?
THE PHYSICS OF MUSIC ♫.
Waves and Sound Examples
14-7 Superposition and Interference
Sound and Music Chapters 20 and 21.
Presentation transcript:

Constructive Interference – Result is a larger amplitude When Two Waves Meet…  Destructive Interference – Result is a smaller amplitude  Waves pass through each other afterwards.  If two waves combine...

Constructive Interference– Waves must be a whole-number wavelength apart Interference by Position  Destructive Interference– Waves must be a half wavelength apart  If you have the same sound but from two different speakers…

Path difference of ½ λ leads to destructive interference Interference by Position  Destructive  Constructive

A real problem for acoustical engineers Dead Zones in Concert Halls Ex. Avery Fisher Concert Hall – Lincoln Center Newly designed concert hall, Minneapolis, MN

Two speakers are 1.00 m apart. A person stands 4.00 m away from one of the speakers. How far must this person be from the second speaker in order to detect destructive interference when the speakers emit a 1150 Hz sound in room temperature air. Example 7

If two sounds are only slightly off in terms of frequency The ‘Beats’  Produce a periodic rise and fall of amplitude (volume)  Throbbing Sound = Beats

#‘beats’ = how far apart the two frequencies are The ‘Beats’  Ex. Tuning Fork 1: f = 440 Hz Tuning Fork 2: f = *Beat Frequency of 2 Hz?

A guitar string produces 4 beats per second when tuned with a 350 Hz tuning fork and 9 beats per second when tuned with a 355 Hz tuning fork. What is the actual frequency of the guitar? Example 8

What about the rubber bands determines pitch? Musical Instruments - Strings  The pitch or frequency of a string is determined by the string’s velocity (how fast it can move back and forth) F T = Force of Tension m/L = (mass)/(Length) = Linear Density  Tension  Thickness