PIRA Classification: 7A10.30
Description: Filters (450, 500, 550, 600, 650 nm) are placed on a light source shining on a PASCO phototube. Connected to the apparatus is a voltmeter which displays the stopping potential for a given wavelength of light. Values of h can be measured within a percent or two (click here to see sample data).
Special Instructions: Don't leave the filters on the light source too long.
Setup time: 2 minutes
Safety Issues: None