Req 10a — Battery, Switch, and Load
This is the simplest complete electrical system you can build: a source, a path, a control, and a load. Even though it is basic, it teaches one of the most important truths in electricity: current only flows when the path is complete.
The Four Essential Parts
Your circuit needs:
- Battery: the power source.
- Wires: the path for current.
- Switch or key: the control that opens or closes the path.
- Load: the buzzer, bell, or light that uses the energy.
If any one of those parts is missing or not connected correctly, the circuit will not work.
How to Think About the Build
Connect one battery terminal to the switch. Connect the switch to the load. Connect the load back to the other battery terminal. That creates a loop.
When the switch is open, the loop is broken and the load stays off. When the switch is closed, current flows and the light, bell, or buzzer activates.
Build and test sequence
A simple way to show your counselor what is happening
- Lay out the parts so you can see the full path.
- Connect the loop from battery to switch to load and back to the battery.
- Test with the switch open to show that nothing happens.
- Close the switch to show the load working.
- Explain the current path out loud while you demonstrate.
This option is a perfect warm-up for Req 10f — Series vs. Parallel Circuits, where you take the same basic idea and compare two different wiring arrangements.