Magnetic Intruder Alarm

Description

A fun build to discover how a magnetic switch works in an electrical circuit!

HOW IT WORKS:
Activate the alarm and close the door. If someone opens the door even a small crack, the alarm will go off. Close the door again or disable the alarm to stop the buzzer.

When the door is closed and the triangles on the magnet slot and base are aligned, the disk is pulled by the magnet to one side of the holed area. When the door is opened, the magnet moves away from the base and the pull from the magnet is no longer strong enough to hold the disc. The disc rolls down to the bottom of the hole area and stays between the two hole plates. This acts like a switch, completing the circuit and allowing current to flow through the buzzer.

CONTENTS:
Part A: Base x 1,  Part B: Cover x 1,  Part C: Magnet x 1,  Part D: Magnet Socket x 1,  Part E: Hole Plate Set x 1,  Part F: Battery Cover x 1,  Part G: Adhesive Tape,  Part H: Metal Disc x 1,  Part Y, End Caps x 3,  Part I: Screws x 3,  Part K: Washer Screws x 2.

Also required but not included in this package: 2x AAA 1.5V batteries, a small screwdriver.