How does a Bulb Work?

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The bulb has a thin wire called a filament, made up of tungsten. Tungsten has a very high melting point, so the filament does not burn even when it gets white-hot. The bulb also contains a gas called argon which does not combine with tungsten to burn out. When we switch on a bulb, electricity passes through the bulb. When it reaches the filament, it makes it hot so that it glows. Actually, the filament resists the flow of electrons. The greater the resistance, the hotter it glows.

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