Title: Waves on a Rope

Purpose:

to determine the differences in fixed and free end rope waves

to investigate the effects of pulse size, hanging mass, rope density, and wavelength on wave speed.

Materials:

Exploration of Physics Simulation: Waves: Waves on a Rope

Procedure:

  1. Wave Speed and Reflection: Fixed End
  2. Set Rope to Fixed End
  3. Set Clock to Auto (Keep at Auto for all Simulations)
  4. Create a small pulse and measure the time required to travel back to the hand.
  5. Record in Table A
  6. Repeat with medium and large waves
  7. Compare/Contrast to free end reflection.
  8. Wave Speed and Reflection: Free End
  9. Set Rope to Free End
  10. Create a small pulse and measure the time required to travel back to the hand.
  11. Record in Table B
  12. Repeat with medium and large waves.
  13. Compare/contrast to fixed end reflection.
  1. Wave Speed and Hanging Mass: Fixed End
  2. Set Rope to Fixed End
  3. Set the hanging mass at 0.5 kg Create a medium pulse and measure the time required to travel back to the hand.
  4. Record in Table C
  5. Repeat by increasing the mass at 0.5 kg intervals as indicated in Table C
  6. Construct a line graph relating mass and time and determine the relationship (if any) between mass and time for fixed end reflection
  7. Wave Speed and Hanging Mass:Free End
  8. Set Rope to Free End
  9. Set the hanging mass at 0.5 kg
  10. Create a medium pulse and measure the time required to travel back to the hand.
  11. Record in Table D
  12. Repeat by increasing the mass at 0.5 kg intervals as indicated in Table D
  13. Construct a line graph relating mass and time and determine the relationship (if any) between mass and time for free end reflection.
  14. Wave Speed and Linear Density of Rope (mass/length ratio): Fixed End
  15. Set Rope to Free End
  16. Set the linear density (mass/length ratio) to 0.01 kg/m
  17. Create a medium pulse and measure the time required to travel back to the hand.
  18. Record in Table E
  19. Repeat by increasing the linear density by 0.2 kg/m intervals as indicated in Table E
  20. Construct a line graph relating linear density and time and determine the relationship (if any) between linear density and time for fixed end reflection.
  1. Wave Speed and Linear Density of Rope (mass/length ratio): Free End
  2. Set the linear density (mass/length ratio) to 0.01 kg/m
  3. Create a medium pulse and measure the time required to travel back to the hand.
  4. Record in Table F
  5. Repeat by increasing the linear density by 0.2 kg/m intervals as indicated in Table F
  6. Construct a line graph relating linear density and time and determine the relationship (if any) between linear density and time for free end reflection.
  1. Wave Speed and Wavelength (k-value: k = 2π/λ): Fixed End
  2. Set Rope to Fixed End
  3. Set the k-value (wavelength function) to1.0 /m
  4. Create a large pulse and measure the time required to travel back to the hand.
  5. Record in Table G
  6. Repeat by increasing the linear density by 1.0 /m intervals as indicated in Table G
  7. Construct a line graph relating k-value and time and determine the relationship (if any) between wavelength and time for fixed end reflection.
  1. Wave Speed and Wavelength (k-value: k = 2π/λ): Free End
  2. Set Rope to Free End
  3. Set the k-value (wavelength function) to 1.0 /m
  4. Create a large pulse and measure the time required to travel back to the hand.
  5. Record in Table H
  6. Repeat by increasing the k value by 1.0 /m intervals as indicated in Table H
  7. Construct a line graph relating k-value and time and determine the relationship (if any) between wavelength and time for free end reflection
  1. Interference: Fixed End
  2. Set Rope to Fixed End
  3. Use Default Settings
  4. Create a series of pulses and see what happens as the waves pass through each other.
  5. You may vary pulse size and frequency, but you MUST RECORD WHAT YOU DO!
  6. Pause and print out ONE (1) interesting pattern
  7. Compare/contrast to interference patterns created with Free End reflection
  1. Interference: Free End
  2. Set Rope to Free End
  3. Use Default Settings
  4. Create a series of pulses and see what happens as the waves pass through each other.
  5. You may vary pulse size and frequency, but you MUST RECORD WHAT YOU DO!
  6. Pause and print out ONE (1) interesting pattern
  7. Compare/contrast to interference patterns created with Fixed End reflection
  8. Standing Waves: Fixed End
  9. Set Rope to Fixed End
  10. Use Default Settings
  11. Send pulses at regular intervals and try to create standing waves.
  12. Comment on ease of creating standing waves!
  13. Compare/Contrast with ease of creating standing waves with Free End reflection
  1. Standing Waves: Free End
  2. Set Rope to Free End
  3. Use Default Settings
  4. Send pulses at regular intervals and try to create standing waves.
  5. Comment on ease of creating standing waves!
  6. Compare/Contrast with ease of creating standing waves with Fixed End reflection

Results: Data Tables and Graphs

Discussion:

  • Summarize what you did.
  • Describe the relationship of wave speed to pulse size, hanging mass, linear density of the rope, and wavelength for fixed end and free end reflection.
  • Compare/contrast fixed end vs free end reflection in relation to pulse size, hanging mass, linear density of the rope, and wavelength.
  • Compare/contrast fixed end vs free end reflection in relation to interference patterns and ease of creating standing waves.

Conclusion: You need several for this lab activity! Remember, they need to be TESTABLE statements!

Reflection: personal commentary about the lab activity.

Judith S. Nuño11/19/2019

Table A: Wave Speed and Reflection
Fixed End / Table B: Wave Speed and Reflection
Free End
Pulse Size / Time (s) / Pulse Size / Time (s)
small / small
medium / medium
large / large
Table C: Wave Speed and Hanging Mass
Fixed End / Table D: Wave Speed and Hanging Mass
Free End
Mass (kg) / Time (s) / Mass (kg) / Time (s)
0.1 / 0.1
0.5 / 0.5
1.0 / 1.0
1.5 / 1.5
2.0 / 2.0
2.5 / 2.5
3.0 / 3.0
3.5 / 3.5
4.0 / 4.0
4.5 / 4.5
5.0 / 5.0
Table E: Wave Speed and Rope Density
Fixed End / Table F: Wave Speed and Rope Density
Free End
Rope Density (kg/m) / Time (s) / Rope Density (kg/m) / Time (s)
0.01 / 0.01
0.03 / 0.03
0.05 / 0.05
0.07 / 0.07
0.09 / 0.09
0.11 / 0.11
0.13 / 0.13
0.15 / 0.15
0.17 / 0.17
0.19 / 0.19
0.20 / 0.20
Table G: Wave Speed and Wavelength
Fixed End / Table H: Wave Speed and Wavelength
Free End
*k-value (1/m) / Time (s) / k-value (1/m) / Time (s)
1.0 / 1.0
2.0 / 2.0
3.0 / 3.0
4.0 / 4.0
5.0 / 5.0
6.0 / 6.0
7.0 / 7.0
8.0 / 8.0
9.0 / 9.0
*k = 2π/λ
Table I: ObservationsInterference Fixed End / Table J: ObservationsInterference Free End
Table K: ObservationsStanding Waves Fixed End / Table L: ObservationsStanding Waves Free End

Judith S. Nuño11/19/2019