Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word:...
-
Upload
gerald-wiggins -
Category
Documents
-
view
217 -
download
0
Transcript of Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word:...
![Page 1: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/1.jpg)
WavesWaves
![Page 2: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/2.jpg)
What is a Wave?What is a Wave?
• A wave is an energy vibration that usually takes place in matter
• Key word: vibration. Waves repeat
• A single “wave” is called a pulse
![Page 3: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/3.jpg)
Wave TypesWave Types
• Transverse Waves vibrate at a right angle to their direction of motion
• Examples: Light, ocean waves, waves on a rope
![Page 4: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/4.jpg)
• Longitudinal Waves vibrate in the direction of motion
• Examples: Sound, P-Waves, “Slinky” Waves
![Page 5: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/5.jpg)
Wave PropertiesWave Properties
• We use four different characteristics to talk about waves: frequency, wavelength, amplitude, period, and speed
• Wavelength is the distance between identical parts of a wave (crestcrest, troughtrough)
• Amplitude is half the wave’s total height, or the distance between the crest and the rest position
![Page 6: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/6.jpg)
Wave TimeWave Time
• A wave’s period is the time it takes for one vibration to occur
• If you divide wavelength by time, you get a wave’s speed (speed = distance/time)
![Page 7: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/7.jpg)
![Page 8: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/8.jpg)
FrequencyFrequency
• A wave’s frequency tells us how often waves occur (2 waves a second, 4 waves a second, etc)
• The units of frequency are Hertz, or Hz
• 1 Hz = 1 wave/second
• Frequency = 1/period
![Page 9: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/9.jpg)
Source or Medium Dependence?Source or Medium Dependence?
• Amplitude?– Source Energy
• Period– Source
• Speed– Medium
• Wavelength– Medium/Source
![Page 10: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/10.jpg)
Some WavelengthsSome Wavelengths
• Microwaves: .03 m
• Radio Waves: 10 m
• Ocean Waves: 200 m
• Tsunami: 11,000 m
• 200,000 m
![Page 11: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/11.jpg)
Two ViewsTwo Views
• Position/Time View– We focus on how one point on the wave
evolves in time
• Snapshot View– We focus on how the wave evolves in multiple
dimension
![Page 12: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/12.jpg)
Time ViewTime View
![Page 13: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/13.jpg)
• Which wave properties can we deduce from this graph?
![Page 14: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/14.jpg)
SnapshotSnapshot
![Page 15: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/15.jpg)
• What can we deduce from this graph?
![Page 16: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/16.jpg)
![Page 17: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/17.jpg)
Interference with Standing WavesInterference with Standing Waves
![Page 18: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/18.jpg)
![Page 19: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/19.jpg)
ResonanceResonance
• Questions of Interest:
• Can you break a wine glass with sound?
• Why did the Tacoma Narrows bridge collapse?
![Page 20: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/20.jpg)
Forced VibrationsForced Vibrations
• Vibrating an object at a specific frequency
• Think back to the lab from last week (part C)
• Forced vibrations can create either organized or unorganized patterns
• On what does the pattern’s organization depend?
![Page 21: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/21.jpg)
Natural FrequencyNatural Frequency
• Most objects (media) have so called natural frequencies
• If we vibrate an object at one or more of its natural frequencies, something interesting occurs
![Page 22: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/22.jpg)
ResonanceResonance
• When a source vibrates an object at its natural frequency, we call it resonance
• You can create large amplitudes with fairly small input
![Page 23: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/23.jpg)
![Page 24: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/24.jpg)
Other Examples?Other Examples?
• Swing sets
• Singing in the shower
• Tuning fork
• Standing waves on spring
![Page 25: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/25.jpg)
Raising the stakesRaising the stakes
• If you continue vibrating something at its resonance frequency, the amplitude of the vibration increases
![Page 26: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/26.jpg)
Shattering a Wine Glass?Shattering a Wine Glass?
![Page 27: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/27.jpg)
![Page 28: Waves. What is a Wave? A wave is an energy vibration that usually takes place in matter Key word: vibration. Waves repeat A single “wave” is called a.](https://reader036.fdocuments.in/reader036/viewer/2022062519/5697bf791a28abf838c8276c/html5/thumbnails/28.jpg)