Light bulbs are essentially resistors inside of a vacuum blub. Why does the filament of a light bulb glow?

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The incandescent bulbs have filaments inside through which current passes through. These filaments are made of Tungsten(W) which has a very high resitance. When current passes through this filament, it gets heated to high temperatures. At higher temperature the filament changes to dark red in color and finally glows in...

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The incandescent bulbs have filaments inside through which current passes through. These filaments are made of Tungsten(W) which has a very high resitance. When current passes through this filament, it gets heated to high temperatures. At higher temperature the filament changes to dark red in color and finally glows in yellowish white color.

 

These resistors are inside a vacuum to prevent from oxidation

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