Asked by: David, Kendal
The glowing beams of light in a plasma ball are the result of electric currents passing through gases like helium and neon at very low pressures. How the beams behave depends on where the current flows begin and end. Many plasma globes feature a central electrode, whose very high-voltage, high-frequency AC electricity creates the currents – and this leads them to flow outwards towards the walls of the globe.
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Authors
Robert is a science writer and visiting professor of science at Aston University. He likes maths, West End musicals and hamsters.
