Worksheet
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Name: ___________________________ Date:_____________ Class:________

Student Worksheet for Frequency and Wavelength

Directions:

Read through the activity, and then using the scientific method, complete the following activity.

  1. Label the transverse wave using defined words.
    Crest
    Trough
    Wavelength
    Frequency
    Amplitude

  2. Problem to be solved:






  3. Hypothesis- predict an answer to your problem, and back up your prediction.




  4. Experiment
    1. Lay your spring on the floor or some other large flat area.
    2. Have a group member hold one end of the spring while another group member holds the other end.
    3. Group members holding the ends should remain this distance for all the trials.
    4. One member is to hold their end of the spring tight and not move their hand.
    5. Trial one: The other group member is to move their end sharply side to side once to create a single wave that travels down the spring.

      *Sound waves travel through the air very much as the spring wave travels down the spring, but sound waves travel faster - about 1/3 Km/sec.
    6. Trial two: Now create a single wave that begins at one end and ends at the other using the spring. Continue to move your hand side-to-side so another team member can mark where the crests of the wave are and mark with clay on the floor. Refer to the defined term, wavelength, to correctly create a complete wave.
      1. Label the single wave sketched below.
      2. Using a meter stick, measure the wavelength and record length on sketched wave in box.
    7. Trial three: Groups should have a group member time 10 seconds on a stopwatch while the group member that is making the wave count the number of single waves, (the number of side-to-side hand movements), they make in the 10 seconds. A group member should mark the distance of one complete wavelength using the clay to mark two crest or two troughs.Using Record findings in #8.
    8. How many times did your hand move side-to-side in 10 seconds?
      (a)._______ hand movements in (b.)10 seconds.

      *The number of vibrations (side to side movements) per second is called the “frequency” of the wave. To find the Unit of frequency use “cycles/sec”, (cycles are the number of hand vibrations (hand movements) in (b.)__ seconds divide by the number of seconds).
      Unit of frequency is also called hertz (Hz)

      a._______ hand movements in 10 seconds
      b._______ number of seconds
      a/b = Frequency = ________Hz
      Wavelength = _______cm **

      ***Students should be creating a single wave crest-to-crest or trough-to- trough for 10 seconds. For wavelength use the meter stick.
    9. Trial four: Now create two full wavelengths and sketch in the box.


    10. Trial five: Now count how many times your hand goes up and down in ten seconds while keeping two full wave lengths on the spring. Have a group member mark the length of one wave and measure with a meter stick.

      Frequency = ________Hz
      Wavelength = _______cm

    11. Trial six: Now create three full wavelengths on the spring.
      Sketch in the box.

    12. Trial seven: While keeping three full wavelengths moving on seconds. Another group member mark the length on one wave, measure and record.

      Frequency = ________Hz
      Wavelength = _______m

    13. Answer these questions:

      1. What are the controls in the trials?




      2. What was the independent variable?




      3. What was the dependent variable?




  5. Conclusion and Communication:
    The group is to discuss “Is there a relationship between a wave’s frequency and its wavelength?”
    Using data they have gathered explain your answer and back it up with the data. Also address your hypothesis. Record your conclusion in a short essay on the back of this worksheet.