Why Do Light Bulbs Blow out?
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2 min read
The incandescent light bulb contains a thin coil of tungsten wire called a filament. This coil has a very high resistance to electricity. When electric current flows through it, it produces heat---in fact, it becomes "white hot."
When any metal becomes this hot it combines with the oxygen in the atmosphere and burns up. To prevent this, all of the air is removed from the light bulb and is replaced with an inert gas such as argon.
If the light bulb is poorly sealed during manufacture or becomes cracked during handling, air will leak into it. The filament will oxidize and burn up, causing the bulb to blow out.
Tungsten is a brittle metal and when drawn into a fine wire it becomes very delicate. When light bulbs are jarred or dropped, the filament can either break completely or become cracked. The bulb will either no longer work, or the filament will quickly fail at its weakest point.
