Finding Plank's Constant Using LEDs

This is a practical which will give an approximate value for Plank's constant. That is a bit different from saying that it's a practical to find Plank's constant! The photoelectric equation is used but the semi-conductor physics involved with LEDs is somewhat different.
That said, this is a useful practical for discussing instrumental uncertainties with single readings as well as the usefulness or otherwise of graphs with small numbers of plots.

The wavelength of the LED light needs to be known beforehand - attempts to measure the wavelength with a spectrometer have given poor results but I would be interested to hear from anyone who tries this with a digital spectroscope.


Ċ
Thomas Carl Pion,
Apr 25, 2015, 1:53 PM
ĉ
Thomas Carl Pion,
May 18, 2015, 2:40 PM
Ċ
Thomas Carl Pion,
Apr 25, 2015, 1:53 PM
ą
Thomas Carl Pion,
Apr 25, 2015, 1:53 PM
ĉ
Thomas Carl Pion,
May 18, 2015, 1:58 PM