PASCO
 
MAIN PROCEDURE
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Windows (.zip file)  |  Macintosh (.sit file)
In this experiment, students will develop a relationship between light intensity and distance from a point source and a line source.
    1. Click the Start button; the Keep/Stop button will appear in its place.

    2. Click the Keep button. A dialog box will appear that will ask you to enter a value for the distance.

    3. Enter the distance between the light bulb and the front of the Light Sensor and click "OK. "

    4. Repeat steps 2-3 for 5.0 cm increments until you have 10 data pairs.

    5. Click the Stop button.

    6. Repeat the Set-Up and Data Collection Procedures for the Point Source.
    1. Using the Fit Button find the appropriate fit from the data for the line source and for the point source.
    DataStudio
    1. What pattern do you notice between the light intensity and the distance from the
      1. Point Source?
      2. Line Source?

    2. What does this pattern tell you about the rate of change in light intensity relative to the change in distance for the
      1. Point Source?
      2. Line Source?

    3. What type of curve fit best approximates the relationship between light intensity and distance from the
      1. Point Source?
      2. Line Source?

    4. Using the equation you found in the Data Analysis section, insert the coefficients you recorded from your graph. Use this equation to predict light intensity at a distance of 1.0 m for the
      1. Point Source.
      2. Line Source.