Wave Search/Notes
Use the following web pages and animations to guide you through the following three main topics.
 Wave interference
 Boundary Interactions
 Standing Waves
This will be your main source of information/notes on this topic. At the bottom of the page there
are a series of questions you need to answer.
Take the time to understand and learn how this works and not just search for answers to the
questions! Please ask questions and work with your neighbors to find the best answers.
These two sites provide good overall information. The Physics Classroom site is specifically written
for high school physics.
http://id.mind.net/~zona/mstm/physics/waves/waves.html
http://www.physicsclassroom.com/Class/waves/
This site has good information, especially for defining terminology. The math goes above what we
are studying but you can use it to look up terms.
http://physics.info/waves/summary.shtml
This site does a good job defining superposition. As you go further down the page the material goes
beyond what we are doing, but the info on superposition is done well.
http://www.acs.psu.edu/drussell/Demos/superposition/superposition.html
This site’s wave section has some good wave animations
http://www.surendranath.org/Apps.html
To use this page, set the wave generator to pulse and damping to 0. You can also use the pause/set
feature to control the wave better. This page lets you really control the wave step-by-step.
http://phet.colorado.edu/simulations/stringwave/stringWave.swf
Use this animation to show how only certain frequencies are able to set up standing waves. Set the
amplitude to max and change frequency one click at a time to see changes.
http://ngsir.netfirms.com/englishhtm/StatWave.htm
Another good standing wave page that links standing waves to harmonics:
http://ngsir.netfirms.com/englishhtm/TwaveStatA.htm
This animation gives great insight into how standing waves are propagated:
http://www.walter-fendt.de/ph14e/stwaverefl.htm
Interference:
1. What is the principle of superposition (In your own words)?
2. What does phase mean and how is it indicated?
3. What is interference?
a. To get constructive interference waves must…
b. To get destructive interference waves must…
4. What would happen if a wave crest and a wave trough of equal amplitude interfered?
5. Wave A has an amplitude of +5 and wave B has an amplitude of -3
a. What will the resulting amplitude be when the waves are superpositioned?
b. What will the amplitude of wave A be after they have crossed each other?
6. If two waves of equal amplitude X interfere with each other what are the two different
maximum possible results? (Answer in relation to X. HINT: the sign of a wave doesn't indicate
amplitude, but phase, so two waves of equal amplitude can have opposite signs.)
Boundary Interactions:
1. What is a boundary, and what two types of boundaries can a wave encounter?
2. What is an incident wave?
3. What is a reflected wave?
4. What is a phase shift?
5. A wave pulse of amplitude +6 is sent into a fixed boundary.
a. What will the reflected wave’s amplitude be?
b. Does the reflected wave undergo a phase shift?
6. A wave pulse of amplitude +6 is sent into a free boundary.
a. What will the reflected waves amplitude be?
b. Does the reflected wave undergo a phase shift?
For questions 7-8, a very thin kite string is connected to a much thicker tow-rope as seen here.
Kite string
Tow-rope
7. You send a wave pulse from the kite string through to the tow rope
a. What will happen in terms of reflection and transmission?
b. Will the reflected portion of the wave come back in-phase or out-of-phase?
8. Now you send the wave pulse from the tow rope through to the kite string
a. Will more of the wave be reflected or transmitted?
b. Will the reflected portion be in-phase or out-of-phase?
Standing Waves:
1. What is a standing wave?
2. How are standing waves generated?
3. What measurements of the reflected wave and the incident wave must be equal to generate a
standing wave?
4. To generate a standing wave the reflected wave and the incident wave must be moving in
________________ direction relative to each other
5. What is a node?
6. What is an anti-node?
7. Draw a standing wave with four nodes and three antinodes.
8. What devices rely on standing waves to function?