The current is the zinc ions in the nail reacting to the copper ions in the wire. Without the potato, the ions woudl just generate heat. The potato buffers the current, and the electrons transfer over the copper wires
Yes it is very much like a flow of water or wind current. In the case of water, it is the water molecules that flow in a pipe. The head or pressure of water is similar to "voltage", the thickness and...
The correct term for the flow of electricity is current. Current is the number of electrons flowing per second in a circuit. The unit of electrical current flow is called the ampere. When 6.28...
If you do this science project you should know that the zinc in the galvanized nail reacts with the phosphoric acid in the potato. This releases electrons.