Planck's Constant Module

One of the projects from the CLEAPSS website resources is to build a small module (circuit) to help determine Planck's Constant.

I have built this up,with a minor modification (for now at least)

  1. The circuit needed 5 LEDs Red, Orange, Yellow, Green and Blue. I have built this up and allowed space for a 5mm Orange LED as i don't at present have one. I do have the other colours, plus importantly the data for each The data information gives me the wavelength in nano meters (nm) for each of the colours.

Photo 1

This is the built up module. I am using a CR2032 to provide the power, I could not find a PCB mountable switch that I wanted for this. So i just soldered on 2x 2.54mm PCB headers and this can be bridged for the switch. Works fine.

The 1k potentiometer works fine along with the 1k resistor I think is there to provide that extra protection to the LED's.

The same image, from a different angle is below

Photo 2

I can't provide a link to the resource for copyright reasons. If you work in a school you will find this project in the Physics resources.