You can build natural disaster alert alarm working models for flood, earthquake, and fire detection using simple components like LEDs, buzzers, and sensors.
1. Flood Alarm Model
Concept: The water level rises and completes a circuit to trigger an alarm.
Materials Needed:
- Water container (tray/bowl)
- Wires
- 9V battery
- Buzzer
- Small metal probes (nails, copper wires, or aluminum foil)
- Cardboard for structure
How It Works:
- Place two metal probes close but not touching in the container.
- When water rises and touches both probes, it completes the circuit.
- The buzzer sounds, indicating a flood alert.
2. Earthquake Alarm Model
Concept: A simple pendulum detects vibrations and triggers an alarm.
Materials Needed:
- Cardboard box
- A small metal ball or pendulum (hanging from a thread)
- Two metal plates (or aluminum foil strips)
- Buzzer
- 9V battery
- Wires
How It Works:
- The pendulum is freely hanging between two metal plates.
- When vibrations occur (simulating an earthquake), the pendulum touches a plate, completing the circuit.
- The buzzer sounds as an alert.
3. Fire Sensor Model
Concept: A heat-sensitive sensor or thermistor detects fire and triggers an alarm.
Materials Needed:
- Thermistor (heat sensor) or candle for testing
- LED light
- Buzzer
- 9V battery
- Wires
- Cardboard for setup
How It Works:
- The thermistor detects heat from fire.
- If temperature rises above a certain limit, the circuit completes, activating the buzzer and LED light.