I will list the questions directly, if you want to know details please read below.
As in the figure, we have water+baking soda in a plastic cup, there are 2 versions in figure that affects LED's brightness and current that flows in circuit.
- In 1st version of figure, LED is bright and more current flows (measured 9.76 mA with multimeter)
- In 2nd version of figure, LED is dull and less current flows (measured 0.22 mA with multimeter)
So my question is, why changing aluminium's place from negative to positive affects current flow of circuit? is it related with aluminium's chemical properties?
Details that explain how i got to this question:
My main aim was to make a home made diode by following instructions in this wonderful site, i did one and it worked.To understand the working mechanism better, i decided to setup things as in the figure upper and faced with this question that looks like main working logic of this home-made diode.In site there was an explanation but i couldn't understand it.