This model shows how a simple electrical circuit can detect water levels.
Water conducts electricity – so when it connects the two metal leads, it completes the circuit and activates the alarm.
This technique is useful for water tank overflow alarms, flood warning systems, and smart irrigation.
Video Steps to Make the Model:
Step 1: Prepare the Base
- Take a cardboard base and stick a small plastic container on it (acts as water tank).
Step 2: Set Up the Circuit
- Connect battery’s positive wire to one sensor pin (pencil lead or metal pin).
- Connect buzzer’s positive terminal to the other sensor pin.
- Connect the negative terminal of buzzer back to battery’s negative end.
- You may use a switch between battery and buzzer for easy control.
Step 3: Fix the Sensor in Container
- Place the 2 pencil leads or pins inside the water container, fixed at a certain height.
- Keep them close but not touching.
- When water rises and touches both leads, it completes the circuit.
Step 4: Test the Model
- Pour water slowly into the container.
- As water touches both leads, the circuit closes, and the buzzer sounds (or LED glows).