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Spherical Mirrors & Index of Refraction
Instructor Notes

 

  • Computers are NOT needed for lab this week
  • Pre-lab demo:
Spherical Mirrors
(L-R) Makeup mirror (plane & shallow concave);
large spherical (concave); small spherical (concave & convex)
The wavy light pipe works best, along with a green laser
 
  • The curved plastic mirror used during the experiment has a very strong magnet attached, so it can grip the paper very tightly without moving
  • The light box should be held close enough to the mirror so that the light rays are dispersed minimally
    • Students will need help aligning the light box to display a second axial ray to determine the center of curvature
  • Students should draw on the blank side of the graph paper. Put a blank sheet of printer paper underneath to make the grid lines easier to see through the page.
  • When using the glass prism, students should aim the beam through the bottom third of the side of the prism. This will give them more room to accurately measure the refraction angles
  • Only one set of ray tracings need to be turned in per group (attached to one report.) Both partners should write up a summary of observations and calculations
  • And, no - they don't know how to properly use a protractor! *Sigh* I've added a picture to the directions showing the correct usage of a protractor. It remains to be seen if this makes any difference at all
  • When everyone is finished, tip over all the flashlights. Students will frequently leave them turned on and place them face-down on the bench, draining the batteries

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Revised: 24 May 2023 Canton, NY 13617