Thin Lenses

Points to Remember During Lab

  1. If your lab section occurs during the day, use Shroeder Hall as your distant object. During daylight hours, Shroeder Hall is illuminated brightly enough to produce a clear image onthe screen of your optical bench. Rotate the bench so that the lens is on a direct line between thewindow and the screen. The night lab section will need to use a bright light as its distant object.
  2. When choosing the three object to screen distances for Procedure #2, be sure that all three aregreater than four times the focal length as measured in Procedure #1.
  3. The lens-maker equation will be used for the larger of the two lenses only. The smaller lenshas a diameter slightly less than that necessary for use with the spherometer.

Points to Discuss in your analysis

  1. Why is using Shroeder Hall better than using an object in the lab room for Procedure #1of this experiment? Discuss the changes in the uncertainty of the focal length measured.
  2. Discuss the uncertainties in the measurement of a and din Procedure #2.
  3. Explain why it was necessary to choose values of d that were greater thanfour times the focal length of the lens.

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