Question

Why does an incandescent light bulb grow dimmer with use?

Answer 1

An incandescent light bulb is a type of light bulb in which the filament is enclosed in air tight glass that avoids oxidation of the filament. When the filament is heated then the bulb glows. Hence when we use this bulb for a long time its brightness is dimmed. Because when the bulb glows some materials of the filament which gets burned out at high temperatures and they fall on the surface of the bulb resulting in black ness of the surface of the glass hence there by it reduces the brightness of the bulb. Also when the material falls of the filament made of tungsten gets weaker and the efficiency is reduced.

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