Group Member Names:                                                              Date ______________

The Universal Stretch!

Lab A Student Worksheet

Materials for Each Group of 3

• 18 - 24 inches of braided elastic, wide enough to sew sequins or buttons on
• 5 Buttons or sequins
• Needle and thread
• Tape measure

Procedure

• Unless your teacher has your one-dimensional Universe (elastic and sequins) prepared for you, sewing must be done first! Take a strip of elastic braid and sew 5 or 6 buttons or sequins on at various distances from one end. This creates a one-dimensional Universe (the elastic), with galaxies (the buttons or sequins) at different distances away from you. Remember, you and your group members will be the observers in this one-dimensional Universe.

• Lay your one-dimensional Universe flat on the table. One group member should be the "Zero Mark", another member should be the "Stretcher" and the last member should be the "Recorder".
• "Zero Mark" should hold one end of the elastic still while the "Stretcher" stretches the elastic a bit. The "Recorder" should record the distance from the "Zero Mark" or end of the elastic to each sequin or "galaxy".
• Record that data in the table below. Stretch the band a cm or so and record your measurements to each "galaxy". This will be considered to be your Initial Distance readings. Then stretch the band between 5 and 10 cm. Record the distance from the Zero Mark to each of the galaxies and enter these data into the second column, Final Distance. Calculate the distance each galaxy "moved" as a result of the stretch. Enter this in the last column.

• Now you are ready to analyze your data. Team members work together. Is there a difference in the distance moved by Galaxy 1 versus the other galaxies? Discuss.
  _____________________________________________________________________
  _____________________________________________________________________
• For each of the 5 galaxies, plot Initial Distance versus Change in Distance caused by the stretch.



• What do you notice about the relationship between how far it moved and the distance at which it started? Discuss.
  _____________________________________________________________________
  _____________________________________________________________________
  _____________________________________________________________________