Today I have done an experiment using lemons to power a clock.
We did this from a set, that contained a small digital clock, two sticks of zinc and three pieces of wire. We had to do is chop the lemon in half. Then we had to get two forks and stick them in both lemon halves. Next, we put the zinc sticks in each lemon half and connected the red wire to 1 of the forks and the black wire to 1 of the zinc sticks on the other lemon half then we connected both these wires to the clock. Then we attached the white wire to the remaining zinc stick and fork. Finally, we Sellotaped the wires in place and the clock started working!
So how does it work?
The forks acts like positive electrodes in a battery. They are plated with metal which doesn’t react as much as the zinc does. When the forks and zinc plates are put into the lemon, a chemical reaction happens. Electrons create a negative charge which moves from the zinc plates to the forks to make a current this switching on the clock. Lemon juice helps conducts electricity this can also be done with potatoes and grapefruit.
Here are my pictures of my potato and lemon clock.
by Joe