Reflection of Wave Lab

Reflection of Waves Lab

Purpose:

In this activity you will be examining the traveling of waves in a string and how the waves reflect from different end points.

Info:

  • To turn the control knobs, click on either the right side of the knob to raise the value or the left side to lower the value.

  • Lab setup




Part 1:  Reflection When String is Tied to C-Clamp
  1. Use the virtual program found here.

  2. Put the frequency at 1.0 Hz, the # waves to 0.5, and the amplitude to 12 cm. Leave the tension at 10 N and the linear density at 5 kg/m.

  3. Send a pulse down the string and pause it when it gets about half way to the c-clamp.  Draw this pulse in your lab book and label it "incident wave".

  4. Resume the motion of the wave pulse and allow it to reflect off the c-clamp.  Watch this reflection closely. 

  5. When the reflected wave reaches the point where it is about half way back to the oscillator, pause the simulation and draw your wave.

  6. Resume the simulation and allow the wave to travel back and forth a few times.  Record what happens to the pulse upon each reflection.

Part 2:  Reflection When String is Attached to a Ring that can move on the clamp.
  1. Leave the frequency at 1.0 Hz, the # waves to 0.5, and the amplitude to 12 cm. Leave the tension at 10 N and the linear density at 5 kg/m.

  2. Reset the system and change the knot to a ring by clicking on the "Change to Ring" prompting in the top left of your program.  This will only be visible when the system has been reset.



  3. Send a pulse down the string and pause it when it gets about half way to the c-clamp.  Draw this pulse in your lab book and label it "incident wave".

  4. Resume the motion of the wave pulse and allow it to reflect off the c-clamp.  Watch this reflection closely. 

  5. When the reflected wave reaches the point where it is about half way back to the oscillator, pause the simulation and draw your wave.

  6. Resume the simulation and allow the wave to travel back and forth a few times.  Record what happens to the pulse upon each reflection.

Part 3:  Speed and Tension
  1. Leave the frequency at 1.0 Hz, the # waves to 0.5, and the amplitude to 12 cm.  Make sure the linear density is set at 5 kg/m.  Toggle on your Ruler.

  2. Create a data table that contains columns for tension, distance travelled, time of travel, and speed.  Make enough rows for 5 sets of data.

  3. Record the tension in the string and then send a pulse down the string.  Stop it at some point right before it reaches the c-clamp.  The more distance you let it travel, the less error you will have in your speed.

  4. Record the distance traveled by the leading edge of the wave (wave front) and the time it took to travel.  Find the speed of the wave.

  5. Change the tension in the string by clicking on the screw of the c-clamp.

  6. Repeat for all possible tensions.

  7. Graph your results.  Graphing program found here.
Part 4:  Speed and Amplitude
  1. Leave the frequency at 1.0 Hz, the # waves at 0.5, the linear density at 5 kg/m, and the tension at 10 N.  Toggle on your Ruler.

  2. Create a data table that contains columns for amplitude, distance travelled, time of travel, and speed.  Make enough rows for 4 trials.

  3. Record the amplitude of the wave in the string and then send a pulse down the string.  Stop it at some point right before it reaches the c-clamp.  The more distance you let it travel, the less error you will have in your speed.

  4. Record the distance traveled by the leading edge of the wave (wave front) and the time it took to travel.  Find the speed of the wave.

  5. Change the amplitude of the wave in the string by using the knob of the frequency generator.

  6. Repeat for all possible nonzero amplitudes.

  7. Graph your results.  Graphing program found here.
Part 5:  Speed and Frequency
  1. Leave the amplitude at 12 cm, the # waves at 0.5,  the linear density at 5 kg/m, and the tension at 10 N..  Toggle on your Ruler.

  2. Create a data table that contains columns for frequency, distance travelled, time of travel, and speed.  Make enough rows for 4 trials.

  3. Record the frequency of the wave in the string and then send a pulse down the string.  Stop it at some point right before it reaches the c-clamp.  The more distance you let it travel, the less error you will have in your speed.

  4. Record the distance traveled by the leading edge of the wave (wave front) and the time it took to travel.  Find the speed of the wave.

  5. Change the frequency of the wave in the string by using the knob of the frequency generator.

  6. Repeat for any 4 frequencies.

  7. Graph your results.  Graphing program found here.
Part 6:  Wavelength and Frequency
  1. Leave the amplitude at 12 cm, the # waves at 1.0,  the linear density at 5 kg/m, and the tension at 10 N.  Toggle on your Ruler.

  2. Create a data table that contains columns for frequency and wavelength.  Make enough rows for 5 trials.

  3. Record the frequency of the wave in the string and then send a pulse down the string.  Stop it at some point before it reaches the c-clamp.

  4. Record the distance between the leading edge of the wave (wave front) and the back of the wave.  This will be the wavelength of the wave.

  5. Change the frequency of the wave in the string by using the knob of the frequency generator.

  6. Repeat for any 5 frequencies.

  7. Graph your results.  Graphing program found here.
Part 7:  Wavelength and Speed
  1. Leave the amplitude at 12 cm, the # waves at 1.0, and the frequency at 2.0Hz.  Make sure the linear density is set at 5 kg/m. Toggle on your Ruler.

  2. Create a data table that contains columns for tension, speed and wavelength.  Make enough rows for 5 trials.

  3. Record the tension in the string and then send a pulse down the string.  You already know the speed for this tension from part 3.  Make sure you record the speed in your lab book.

  4. Stop it at some point before it reaches the c-clamp.

  5. Record the distance between the leading edge of the wave (wave front) and the back of the wave.  This will be the wavelength of the wave.

  6. Change the tension in the string by clicking on the screw of the c-clamp.

  7. Repeat for all 5 tensions.

  8. Graph your results.  Graphing program found here.
Part 8:  Speed and Linear Density
  1. Leave the frequency at 1.0 Hz, the # waves to 0.5, and the amplitude to 12 cm.  Make sure the tension is set at 10 N.  Toggle on your Ruler.

  2. Create a data table that contains columns for linear density, distance travelled, time of travel, and speed.  Make enough rows for 5 sets of data.

  3. Record the linear density of the string and then send a pulse down the string.  Stop it at some point right before it reaches the c-clamp.  The more distance you let it travel, the less error you will have in your speed.

  4. Record the distance traveled by the leading edge of the wave (wave front) and the time it took to travel.  Find the speed of the wave.

  5. Change the linear density of the string by clicking on the string after the system has been reset.

  6. Repeat for all possible linear densities.

  7. Graph your results.  Graphing program found here.

Comments