Insulators have valence shells that are more than half full of electrons and, as such, are tightly bound to the nucleus and difficult to move from one atom to another.

Connecting the 10 batteries in series multiplies their voltage while keeping their current the same yielding a 120V 25A configuration. Connecting the 10 batteries in parallel multiplies their current while keeping their voltage the same yieleding a 12V 250A configuration. Using a series-parallel connection, 5 batteries can be connected in series and 5 can be connected in parallel resulting in a 60V 125A configuration.

A closed circuit is a complete loop or path that electricity follows. It consists of a source of voltage, a load, and connective conductors. If the circuit is interrupted, if a wire is disconnected or cut for example, it becomes an open circuit and no electricity will flow.

You can multiply the voltage or the current supplied by individual batteries by connecting them together either in series or in parallel. The characteristics of batteries connected in series are that total voltage equals the sum of the individual battery voltages, total current equals the average of the individual battery currents, the positive terminal of one battery is connected to the negative terminal of the next, and one connection is made between each adjacent battery.

A moving electric current produces a magnetic field proportional to the amount of current flow. This magnetic field can be made stronger by winding the wire into a coil and further enhanced if done around an iron containing (ferrous) core.