Combining Waves interference § 14.7 1.

Slides:



Advertisements
Similar presentations
Topic 11 – Wave Phenomena.
Advertisements

Waves Energy can be transported by transfer of matter. For example by a thrown object. Energy can also be transported by wave motion without the transfer.
Wave interactions.
The Organ Pipe.  During the last two labs you explored the superposition of waves and standing waves on a string.  Just as a reminder, when two waves.
ISAT 241 ANALYTICAL METHODS III Fall 2004 D. J. Lawrence
Wave Properties Chapter 14.
Principle of Superposition Interference Stationary Waves
7/5/20141FCI. Prof. Nabila M. Hassan Faculty of Computer and Information Fayoum University 2013/2014 7/5/20142FCI.
Chapter 18 Superposition and Standing Waves. Waves vs. Particles Waves are very different from particles. Particles have zero size.Waves have a characteristic.
Waves and Sound AP Physics 1. What is a wave A WAVE is a vibration or disturbance in space. A MEDIUM is the substance that all SOUND WAVES travel through.
Waves and Sound Ch
Harmonics Physics Chapter 13-3 Pages A. Standing waves on a vibrating string Fundamental frequency – lowest frequency of vibration of a standing.
Chapter 14 Superposition and Standing Waves 2 Waves vs. Particles Particles have zero sizeWaves have a characteristic size – their wavelength Multiple.
THE PHYSICS OF MUSIC ♫. MUSIC Musical Tone- Pleasing sounds that have periodic wave patterns. Quality of sound- distinguishes identical notes from different.
Waves A wave is a rhythmic disturbance that carries energy through matter or space.
Physics 1C Lecture 14A Monday Quiz Topics: Mass on a spring Mass on a string = simple pendulum Equation for simple harmonic motion Energy in oscillations.
Chapter 18 Superposition and Standing Waves. Waves vs. Particles Waves are very different from particles. Particles have zero size.Waves have a characteristic.
Stationary Waves Stationary waves are produced by superposition of two progressive waves of equal amplitude and frequency, travelling with the same speed.
FCI. Faculty of Computers and Information Fayoum University 2014/ FCI.
Waves. Wave: A disturbance that is transmitted from one place to the next with no actual transport of matter. All waves start with a vibration. All waves.
Copyright © 2009 Pearson Education, Inc. Lecture 1 – Waves & Sound b) Wave Motion & Properties.
Wave Motion. Conceptual Example: Wave and Particle Velocity Is the velocity of a wave moving along a cord the same as the velocity of a particle of a.
12-3 Properties of Waves.  A wave is the motion of a disturbance.  Waves of almost every kind require a material medium to travel through.  Waves that.
Waves. Opening scene from: Billabong Odyssey Wave Properties Wave – A rhythmic disturbance that carries energy through matter or space. Pulse – Single.
Ch17. The Principle of Linear Superposition and Interference Phenomena
What is a wave? A wave is the motion of a disturbance.
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.
Physics. Wave and Sound - 4 Session Session Objectives.
Superposition and Standing Waves
Sound Intensity Energy flux at your eardrums § 16.3.
Wave Interference Superposition Principle – when two or more waves encounter each other while traveling through a medium, the resultant wave is found by.
Waves and Sound Honors Physics.
For a standing wave to be set up in a string there has to be two waves travelling in it. Explain what has to be the same and what has to be different about.
Stationary Waves Stationary waves are produced by superposition of two progressive waves.
Group Work 1.Add these two waves together.. Waves Part 2: resonance and more dimensions.
Chapter 15: Wave Motion 15-2 Types of Waves: Transverse and Longitudinal 15-3 Energy Transported by Waves 15-4 Mathematical Representation of a Traveling.
 Wave energy depends on amplitude, the more amplitude it has, the more energy it has.
FCI. Faculty of Computer and Information Fayoum University FCI.
Wave Interference and Standing Waves. Interference Constructive interference – Peak and peak – Trough and trough += Destructive interference – Peak and.
SOUND.
Lecture 11 WAVE.
Chapter 15 Mechanical Waves.
Interference Of Waves.
Section 3: Wave Interactions
Hearing Biomechanics Standing waves.
Principle of Superposition Interference Stationary Waves
Mechanical Wave Interactions
Active Figure 18.4 The superposition of two identical waves y1 and y2 (blue and green) to yield a resultant wave (red). (a) When y1 and y2 are in phase,
Wave Behavior in Sound Waves and Resonance!
Whiteboard Work A child on a playground swing makes a complete to-and-fro swing every 2 seconds. What is the frequency of the swinging? What is the period.
General Physics waves_2
Damping Sometimes engineers don’t want springs to keep oscillating.
Interference.
Standing waves.
WAVES.
بسم الله الرحمن الرحيم FCI.
Superposition of Waves
Vibrations and Waves Wave Interactions.
Wave Interactions.
Vibrations and Waves 12-3 Properties of Waves.
General Physics waves_diffrac diffraction
Chapter 16: Sound HW2: Chapter 16: Pb.2, Pb 18, Pb.24, Pb 35, Pb.40, Pb.62 Due on Wednesday 24.
THE PHYSICS OF MUSIC ♫.
Principle of Linear Superposition and Interference Phenomena
14-7 Superposition and Interference
Vibrations and Waves Wave Interactions.
SCI 340 L39 Wave interference
Waves and Sound PHYS 1090 Unit 7.
Combining results gives us the case where both observer and source are moving:
Interference Of Waves.
Presentation transcript:

Combining Waves interference § 14.7 1

Principle of Superposition Where waves meet, the displacement is the sum of the displacements from the individual waves. 3 Run at: W1 = 0.2; k1 = 0.2; ampl = 15 integral multiples (half, third, quarter) of lambda: multiply W1, k1 by 2, 3, 4 add same-lambda wave with negative amplitude Beats: slightly vary w2 and k2 together from wave 1 values Standing waves (use phase velocity of 0.5: k = 2*w) result –3

Interference Constructive: Sum of waves has increased amplitude Destructive: Sum of waves has decreased amplitude Two-wave simulation

Interference Patterns Interference of similar wavelengths 4

Patterns Positions of constructive and destructive interference destructive: nodes constructive: antinodes Ripple tank simulator http://www.falstad.com/ripple/

waves that don’t actually travel Standing Waves waves that don’t actually travel § 14.8 6

Standing Waves Sum of waves of equal amplitude and wavelength traveling in opposite directions Half-wavelength divides exactly into the available space Wave pattern has locations of minimum and maximum variation (nodes and antinodes) (standing longitudinal waves) Run at: w1 = 0.2; k1 = 0.2; ampl = 15 integral multiples (half, third, quarter) of lambda: multiply w1, k1 by 2, 3, 4 add same-lambda wave with negative amplitude Beats: slightly vary w2 and k2 together from wave 1 values (0.22 and 0.22; 0.21 and 0.21, etc.) Standing waves (use w of about 0.2; try w = 0.2, k = 0.1) 7

standing waves generalized Normal modes standing waves generalized 8

Modes Objects have characteristic frequencies at which standing waves are sustained Lowest frequency = fundamental Higher frequencies = overtones Sustained motion is a combination of normal modes 9

Vibrational Modes: Clamped String Insert Figure 15.3 from class text Source: Griffith, The Physics of Everyday Phenomena, Figure 15.13 10

Combinations of Harmonics Characteristic sounds arise from combining particular harmonics in specific ratios Fourier analysis suimulation flute oboe saxophone Simulation

“Closed” and “Open” Tube Modes Source: Halliday, Resnick, and Walker, Fundamentals of Physics, 2003, p 419.

Sequence of Harmonics Western musical scale and harmonies are based on overtone series (sound files) Sound files: overtones of open tube or clamped string

Circular membrane standing waves 2-D Standing Waves Nodes are lines or curves Circular membrane standing waves edge node only diameter node circular node Source: Dan Russel’s page Higher frequency  more nodes

Aside Electron orbitals in atoms and molecules are 3-D standing waves All particles have wave natures Orbitals are interference patterns that persist (don’t cancel over time) Stationary states are like harmonics

Resonance Boundary conditions determine nodal positions For uniform media, resonant wavelengths and frequencies have simple relationships Clamped strings http://www.surendranath.org/Applets/Waves/Harmonics/HarmonicsApplet.html Air cylinders http://www.physics.smu.edu/~olness/www/05fall1320/applet/pipe-waves.html More complex media are more interesting http://paws.kettering.edu/~drussell/Demos.html 16

coincidence of similar frequencies Beats coincidence of similar frequencies § 14.9 17

Beats Waves of similar frequency combine to give alternating times of constructive and destructive interference Distinctive “waa-waa” sound with beat frequency equal to the difference in frequency of the component waves fbeat = |f1 – f2| (Why?)

Beats Sound files Ripple tank simulator http://www.falstad.com/ripple/