BackGround Research
I've learned why the potato powered the L.E.D light. The potatoes powered the L.E.D because the zinc from the galvanized steel nail and the copper from the pennies acted as the anode and cathode terminals of my battery. I used an ordinary electric wire to connect the potatoes together. That means I just created a voltaic cell that can power the L.E.D. Of course the potatoes only has 1.5 volts. This kind of battery can only produce a few milliamps. The potatoes are not powerful enough to power a normal household lightbulb, but the potatoes can light up a small flashlight. The penny and the galvanized steel nail can't touch each other. If it does touch, then the battery won't work. If the nails and the pennies are connected to a series of wires, then that will create electrons that will flow through the wires which will make the L.E.D light up. Electric current is the movement of electrons from one atom to another in a condutor. That's why if you connect the galvanized steel nails and the pennies in a series of wires, that will make an L.E.D light up.