Category Archives: Atomic Physics

Transmission and Absorption

Demo: MP-B-TA
Pira Index: 7B 11.00

 Lab Equipment  Directions
  1.  Pasco blazed diffraction grating
  2. 4 slit slides with cuvettes
  3. prism lab stand
  4. 90 degree clamp
  5. slide projector
  1.  Place the clear cuvette slide into the slide projector. Set the stand with the diffraction grating in front of the projector. You will see 2 complete spectra on the screen (one above the other).
  2. Remove the clear slide and replace with the red filter cuvette. Notice that only the red part of the spectra comes through on the bottom spectra.
  3. Repeat with the blue and green filters.


He Ne Laser Spectra

Demo: MP-B-HN
Pira Index: 7B 10.10

 Lab Equipment  Directions
  1.  Helium spectra tube
  2. Neon spectra tube
  3. 2 Spectra power supplies
  4. HeNe red laser (special one with plexiglass top)
  5. diffraction gratings (1 for each student)
  6. plug strip
  7. cylindrical diffraction screen
  1.  Place spectra tubes into the power supplies. Carefully stack the two power supplies and turn them on.
  2. Turn on the laser and hold the open window of the laser above the power supplies.
  3. Have students look through the gratings at each spectra and compare.
  4. Notice that the individual spectra are combined in the HeNe laser.


Atomic Spectrum

Demo: MP-B-AS
Pira Index: 7B 10.10

 Lab Equipment  Directions
  1.  Spectrum tube power supply
  2. Spectrum tubes (hydrogen, helium, neon, mercury)
  3. diffraction gratings (approx. 40)
  4. variac
  5. showcase bulb in wood base
  6. lab jack
  7. cylindrical diffraction grating
  1.  Mount tube in power supply.
  2. Turn on power supply.
  3. View tube through grating.