Wire Loop Game

Step 4 About Circuits

A circuit is a pathway that carries electricity from one end of a battery to the other. Chemical processes inside the battery create a pressure known as voltage that pushes electricity forward whenever a complete pathway is present. If the pathway is broken at any point, no electricity flows through the circuit. This is what happens when you shut off any battery-operated device: the circuit is interrupted, and electricity stops flowing.

In circuits with batteries, electricity always flows from the end of the battery marked with a minus sign (-), called the negative or ground end, to the end marked with a plus sign (+), called the positive or power end. In most cylinder-shaped batteries, including the AA batteries used in this project, the power end has a small raised tip, whereas the ground end is flat. Figure 3 shows a simple circuit, with a battery and a light bulb.