An electrical circuit is a closed path through which a flow of electrons passes through. A simple circuit consists of a power source (such as a battery), cables, and a resistor (a light bulb). The electrons travel from the battery through the electrical wires and reach the bulb. When it receives a sufficient amount of electrons, it lights up. If you follow the instructions correctly, you too will be able to turn on a light bulb with a few simple steps.
Steps
Part 1 of 3: Building a Simple Circuit with a Battery
Step 1. Gather all the necessary materials
To make a simple circuit, you will need a power source, two insulated electrical wires, a light bulb and a lamp holder. You can use any type of battery or battery pack as a power source, while the rest of the material is also available in hardware stores.
- When choosing your light bulb, consider how much power the battery can deliver.
- To simplify the process of connecting cables, choose a push connector with pre-fitted wires and a 9-volt battery.
Step 2. Strip the ends of the insulated wires
In order for the circuit to function perfectly, the electrical wires must be exposed, so you must remove the insulating sheath at the ends. You can use a wire stripper and remove about 2.5cm of the sheathing at the end of each cable.
- If you don't have this type of pliers, you can use regular scissors, but be very careful.
- Make sure you don't cut the entire section of the cable.
Step 3. Insert the batteries into the battery holder
Depending on the type of battery you are using, this step may not even be necessary. If you have decided to use a battery pack, then you will need a suitable battery holder. Insert each stack with the correct positive and negative poles oriented.
Step 4. Connect the cables to the battery holder
These have the function of conducting electricity to the bulb. The simplest technique is to use insulating tape. Place the end of a wire on one pole of the battery, making sure it maintains contact with the metal part. Repeat the process with the other cable for the opposite pole of the battery.
- Alternatively, if you have decided to use a push connector, connect the "button" part of the push connector onto the battery or 9 volt assembly.
- Be very careful when assembling the circuit. Although unlikely, it is always possible to get a very small electric shock when you touch a wire connected to the battery. To prevent this from happening, just touch the insulated portion of each wire or disconnect the battery while mounting the bulb.
Step 5. Secure the other end of the wire to the metal screw of the lamp holder
Model the bare part of the electrical cable giving it a "U" shape. Loosen each screw on the socket just enough to insert the wire under it so that the "U" wraps around the screw stem. Tighten the screw making sure that the bare part of the cable remains in contact with the screw.
Step 6. Test the circuit
Insert the bulb into the socket and screw it in until it stops. If the circuit has been assembled correctly, the bulb should light up as soon as it is fully screwed in.
- Bulbs reach high temperatures quickly, so be very careful when inserting and unscrewing them.
- If the light does not come on, check that the cables are touching the battery poles and the metal part of the screws.
Part 2 of 3: Install the Switch
Step 1. Get the material
To add a switch, you need three pieces of wire instead of two. Once you have peeled them and attached them to the battery, you can proceed to install the switch.
Step 2. Insert the switch
Take the stripped end of a cable connected to the battery and bend it into a "U". Loosen a screw on the switch and insert the bent part of the cable under its head. Tighten the screw again so that the bare part of the wire remains in contact with the shaft of the screw.
Step 3. Connect the third wire to the switch
Bend both ends without sheath into a "U". Thread one under the second screw of the switch to connect it to it. Screw it in to make sure that the metal part of the cable remains in contact with the screw itself.
Step 4. Attach the bulb
Take the end of each cable (one coming directly from the battery and the other from the switch) and bend it into a "U". Loosen both socket screws just enough to tuck the curved bare wire under their heads. Each wire must be connected to a screw. Tighten the screws making sure the cables make contact with the metal part.
Step 5. Test the circuit
Screw the bulb firmly into the socket. Hit the switch! If the circuit has been assembled correctly, the light bulb should light up.
- Bulbs reach high temperatures quickly, so be very careful when screwing and unscrewing them.
- If the bulb does not light up, check that the cables are connected to the battery poles and to the metal part of the screws.
Part 3 of 3: Troubleshooting
Step 1. Make sure all cables are properly connected
To close the circuit, the wires must touch the metal parts of each component. If the light bulb does not light up, check the battery posts and screws on the socket to make sure metal elements are making contact with the wires.
- Make sure the screws are tight to ensure contact.
- In some cases, you will need to remove more of the insulation.
Step 2. Check the filament
If this is broken, the bulb will not light up. Hold it against the light and check that the filament is well fixed and intact. Try replacing the bulb with a new one, and if that's not the source of the problem, follow the instructions in the next step.
Step 3. Make sure the battery is charged
If it is "dead" or low on charge, it does not have enough power to light the bulb. Test it with a tester and replace it with a new one if necessary. If this is the source of the problem, the bulb should come on once the change is made.
