The simple circuit

If the children do not assemble the circuit as shown in the diagram, the light will not light up as the current only flows in one direction.

The experiment is assembled as shown in the photo.

• a battery,
• a champagne cork,
• a film can,
• a bottle cap,
• three wires,
• a small lamp,
• a small screw,
• a thumbtack,

The wires must be connected correctly, otherwise the current cannot flow.

What is technically behind the experiment

The electric current that flows in a conductor consists of electrons that all move in a preferred direction. The electrons that produce the current come from the atoms of the conductive metal. The atoms of the copper wire, which are arranged regularly, contain 29 electrons. At room temperature, each copper atom can emit one electron, namely the one furthest away from the atomic nucleus. The "free" electrons move back and forth very quickly in the empty spaces between the atoms. In the process, one is sometimes recaptured by a copper atom and another is released. The result is that there is an approximately constant number of free electrons between the metal atoms. If we now apply a voltage to the copper wire, the electrons move in one main direction. We obtain an electric current. If we interrupt the wire, the current flow stops.

What the experiment has to do with everyday life

In this experiment, the children get to know the simple electric circuit, which is rarely found in this form in the household, but is the basis for the other electric circuits. The children can now also better understand the expression "the current flows", which adults often use. Many children were probably not yet aware that electricity only flows in one direction.

Sandra Resa