Making a simple circuit is a hands-on method of understanding how energy is generated from the movement of electrons through a “conductor,” and can be done at home with inexpensive materials. Electrons are the negatively-charged particles which orbit the positively charged protons (contained within the nucleus) in an atom, and a “current” composed of moving electrons is known as electricity. Technically speaking, current will flow if you simply attach a wire to either terminal of a battery, but for a better visual display a light bulb and even a switch can be incorporated into your circuit.
Cut the wire into pieces using the wire cutters. If you’re using a switch, you’ll need three pieces, with one roughly the same length as the remaining two pieces combined. For simpler circuits (with just a bulb), you only need two pieces of equal length. Strip around 1 cm (or roughly 1/2 an inch) of insulation from either end of each piece of wire, exposing the bare copper.
Place the bulb and battery into their respective holders. Mount these onto the wooden block and screw the holders into place using your screwdriver. You can also mount the knife switch onto the block if you’re using one. The position of each component of the circuit doesn’t really matter, but for aesthetic purposes you can make them more closely resemble a schematic diagram by using a rectangular arrangement. Position the bulb and battery on the short sides and the switch on one of the longer sides.
Connect the wires to each component of your circuit. The copper in the wires carries the electrons stored at the negative terminal of the battery (the flat side) to the abundance of protons at the positive terminal. The difference between these two points is known as the voltage difference, or simply “voltage” for short. Loosen the screws on either side of the bulb holder, insert the tips of two wires and tighten the screws, so the wires are in contact with either side of the metallic bridge. Press the spring on each side of the battery holder clip to open a loop for the end of your wire and release it when the wire is inserted. Depending on the specific switch or battery holder you bought, you may need to secure the wires with a screw.
Close the knife switch to activate your circuit and illuminate the bulb. If you aren’t using a switch, the bulb will light up as soon as you create a circuit with it and the battery. The electrons flow from the negative terminal of the battery, through the wire (and the switch) and to the bulb, where its “resistance” converts some of the energy to light. Break the circuit to turn off the bulb.
Be careful not to make contact with the metal when connecting the final wire of your circuit, since the current could flow into you. If you have a switch, make sure it's off (not connected) until you've completed the circuit.
Tips and warnings
- Be careful not to make contact with the metal when connecting the final wire of your circuit, since the current could flow into you. If you have a switch, make sure it's off (not connected) until you've completed the circuit.
Things you need
- 1.2 volt light bulb
- Light bulb holder (bridge mounting)
- Size D battery
- Size D battery holder
- Insulated copper wire
- Wire cutters
- Wooden base
- Knife switch (optional)