PIRA: 6A61.20


 Lab Equipment  Directions
  1.  Pasco 9117 variable diaphragm
  2. PVC tube with diaphragm holder
  3. PVC tube with foil and 3 pinholes
  4. filament viewing lamp
  5. lens tube
  1.  Plug in the lamp and turn off the room lights.
  2. With lens tube in the viewing lamp, focus image onto the wall by moving lens tube in and out.
  3. Remove lens tube and replace it with PVC tube and diaphragm. Observe what happens as the diaphragm is open and closed.
  4. Replace tube and diaphragm with pinhole PVC tube. Alternately cover each of the pinholes with a finger noting which is brighter or clearer.