Having started to learn about quantum behavior, this formula came up:
$$E = hf $$
Where $E$ is energy, $h$ is the Planck constant and $f$ is the frequency.
My physics teacher suggested an experiment involving LEDs as a way of calculating $h$.
However given that the Planck constant was calculated long before the invention of LEDs, how was it calculated? I know from doing some research Planck used something to do with black body radiation, but I cannot seem to find out the specifics of his method.