PURPOSE: Projected line diffraction spectrum of high-pressure sodium lamp.
DESCRIPTION: A low-pressure sodium lamp is used to project the line spectrum of sodium. This one is not real bright, but can be seen if the screen isn't too far away. The advantage is that because it operates at a lower temperature it shows the emission lines nicely.
The light is defined by a slit, which is imaged on a distant screen after the light passes through the diffraction grating. Gratings of 2000 and 7500 lines per inch are furnished.
REFERENCES: (PIRA unknown.)
EQUIPMENT: Low-pressure sodium lamp, slit, 20 cm focal length convex lens, and 2000 and 7500 line per inch gratings.
SETUP TIME: None. (Lamp requires 15 minute warm-up time.
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