Physics

The Multi-Wire Spark Detector provides a memorable and dramatic demonstration of the ionising properties of alpha radiation, making one of the key concepts in Nuclear Physics both visible and audible. Fine wires suspended above a metal plate form two electrodes separated by a small air gap. When a high voltage is applied, ionisation caused by alpha particles triggers bright, audible sparks. Bringing an alpha source (e.g. Americium) close to the detector produces a dramatic display of sparking, clearly demonstrating the highly ionising nature of alpha radiation as well as its short range and low penetrating power.