G Waves Lab

A: Tension and velocity: (Any open area)

1. Part 1

   1. While standing, take a small spring and stretch it to a length of 7 feet (1 floor tile is 1 foot) Have your third person stand in the middle to watch the pulses.

   2. Send a pulse down the spring. (Pluck the string like you are playing a bass)

   3. Stretch it to 14 feet

   4. Send a pulse down the spring

2. Part 2

• 1. Click Here to launch the "Wave on a String" PhET

  2. Click the play button to run the PHET

  3. Select "Pulse", "No End", on the top, "Normal" in the middle bottom, and move the slider for damping to "None" and the slider for "Tension" to "High"

  4. Click the green circle on the pulse device, and send a pulse down the string

  5. Move the slider for tension to "Low".

  6. Click the green circle on the pulse device, and send a pulse down the string

3. Which is faster? (The high tension or the low)

B: Wavelength and frequency (Use the mondo spring in the front of the room)

1. Part 1

   1. Hold the end right next to the clock

   2. Try wiggling the spring up and down slowly

   3. Try doing it quickly

2. Part 2:

• 1. Click Here to launch the "Wave on a String" PhET

  2. Click the play button to run the PHET

  3. Select "Oscillate", "No End", on the top, "Normal" in the middle bottom, and move the slider for damping to "None" and the slider for "Tension" to the middle. Have your amplitude at 0.75.

  4. Try varying the "Frequency" from 0.70 Hz to 3.00 Hz using the slider at the bottom.

3. What is the relationship between frequency and wavelength? (As you increase frequency, what happens to the wavelength, as you decrease frequency, what happens)

C: Wavelength and Wavespeed (Use a Chromebook at your desk)

1. Click Here to launch the "Wave on a String" PhET

2. Click the play button to run the PHET

3. Select "Oscillate", "No End", on the top, "Normal" in the middle bottom, and move the slider for damping to "None"

4. Have your amplitude at 0.75

5. Try varying the "Tension" from "Low" to "High" using the slider at the bottom. The High tension gives you a high wavespeed, and the Low, a low.

6. What is the relationship between wavespeed and wavelength?

7. (As you increase wavespeed (With High tension), what happens to the wavelength, as you decrease wavespeed (With Low Tension), what happens)

D: Reflections (Use a Chromebook, work at your desk)

1. Click Here to launch the "Wave on a String" PhET

2. Click the play button to run the PHET

3. Select "Pulse", "Fixed end", on the top, "Normal" in the middle bottom, and move the slider for damping to "None" and the slider for "Tension" to the middle.

4. Click the green pulse button to send a pulse down the string. Watch as it reflects off of both fixed ends.

5. What happens to the pulses as the reflect off the Fixed ends? (Do they reflect upright or inverted?)

6. Click the "Restart" button at the top, and on the top right click "Loose End"

7. Click the green pulse button to send a pulse down the string. Watch as it reflects off of the free end on the right.

8. What happens to the pulses as the reflect off the loose (Free) end? (Do they reflect upright or inverted?)

E: Types of waves (Do this on one of the tables in the room)

1. Watch this video : https://www.youtube.com/watch?time_continue=7&v=_2HE4AlSE_s (Turn up the volume)

2. Make those waves with a small slinky. (Stretch it out about 7 feet - lay it on a table in the room)

3. In your own words, write a definition of a longitudinal wave, and a transverse wave

F. Superposition (Do this on the floor in the hall outside the room)

1. Watch this video: https://www.youtube.com/watch?v=ypcX1LdmMPM
2. Watch this video: https://www.youtube.com/watch?v=QjukfQttKAQ

3. Do that with the cups - set them out in the hall 2 feet apart. Stretch a big slinky out 20 feet in the hall.
Send two pulses that constructively interfere, and knock one of the cups to the side, leaving the other
Send two pulses that destructively interfere right where the cups are, leaving them both un-disturbed