Waves. The Nature of Waves – What’s in a Wave – Waves and Energy – Mechanical Waves.
Waves
-
Upload
warren-hines -
Category
Documents
-
view
16 -
download
0
description
Transcript of Waves
![Page 1: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/1.jpg)
Waves
![Page 2: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/2.jpg)
Opening scene from:
Billabong Odyssey
![Page 3: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/3.jpg)
Wave Properties
• Wave – A rhythmic disturbance that carries energy through matter or space.
• Pulse – Single ‘bump’ / disturbance that travels through medium.
• Medium – matter (or lack thereof) through which waves travel.
![Page 4: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/4.jpg)
Transverse Waves• Wave that vibrates medium perpendicular to
direction of wave motion.
![Page 5: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/5.jpg)
Longitudinal Wave• Wave that vibrates medium parallel to
direction of wave motion.
Sound
Molecules resonating in a closed pipe
![Page 6: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/6.jpg)
Water waves are a combination of transverse and longitudinal.
Combination Waves
![Page 7: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/7.jpg)
Great Men Who Lived Among Waves
Duke Kahanamoku
Eddie Aikau
![Page 8: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/8.jpg)
Measuring a Wave
• Amplitude
• Period
• Frequency
• Wavelength
• Velocity
![Page 9: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/9.jpg)
![Page 10: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/10.jpg)
![Page 11: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/11.jpg)
Waves at BoundariesIncident Wave
Reflected Wave Transmitted Wave
Wave Motion
Wave MotionWave Motion
Before
After
![Page 12: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/12.jpg)
Waves at Boundaries• From Low Density to High Density
Reflected ‘Inverted’, Transmitted ‘Upright’
Animations courtesy of Dr. Dan Russell, Kettering University
![Page 13: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/13.jpg)
Waves at Boundaries• From High Density to Low Density
Reflected ‘Upright’, Transmitted ‘Upright’
![Page 14: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/14.jpg)
Superposition of Waves• Superposition: When 2 waves cross paths.
• Principle of Superposition: When 2 waves meet, the new wave formed is the sum of the two incident waves.
• Interference: the result of wave superposition.
•Link to Superposition animationWave Interference Animations
![Page 15: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/15.jpg)
• 2 waves of same frequency, same direction, different speeds.
• Varying constructive and destructive interference
• 2 waves of same frequency, different direction, same speeds.
• Result is a standing wave (note what’s called the node and anti-node)
• 2 waves of slightly different frequency, same direction, same speeds.
• Result is known as ‘beat’ oscillation.
![Page 16: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/16.jpg)
Standing Waves• Standing waves occur when 2 waves of identical frequency and
speed interfere with one another while travelling in opposite directions.
Node: Point on a wave that doesn’t move.
Anti-Node: Point on wave that moves the most.
![Page 17: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/17.jpg)
Harmonics
1st Harmonic (The Fundamental)2nd Harmonic
3rd Harmonic
Harmonics: Where frequencies are ‘nice’ multiples of the fundamental frequency.
![Page 18: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/18.jpg)
Harmonic # of Nodes # of Antinodes Pattern
1st 2 1
2nd 3 2
3rd 4 3
4th 5 4
5th 6 5
6th 7 6
nth n + 1 n --
Harmonics
![Page 19: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/19.jpg)
![Page 20: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/20.jpg)
Mode Diagrams for Circular Membranes
Diagram Mode Desig. Rel. Frequency Diagram Mode Desig. Rel. Frequency Diagram Mode Desig. Rel. Frequency
![Page 21: Waves](https://reader035.fdocuments.us/reader035/viewer/2022070400/568134b2550346895d9bcf20/html5/thumbnails/21.jpg)
How the Vortex Gun WorksWhen you throw a rock through the air, the air moves around it.
http://amasci.com/wing/smring.html