WHY do light bulbs tend to explode when they burn out?

The filament of an incandescent bulb heats up to about 2000 °C. It oxidizes and degrades quite quickly in the air at this temperature. That is why the air is evacuated from the bulbs.

Yet if a small crack appears in the bulb through which air penetrates, it heats up sharply when the lamp is turned on and the increased pressure can destroy the bulb. Almost at the same moment the coil, which was in the air environment, burns out.

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