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Why are filaments of incandescent lamps ...

Why are filaments of incandescent lamps made of thin tungsten wire ?

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Tungsten has low resistivity and as such only a thin wire filament will high resistance necessary to produce large amount of heat to light the bulb brilliantly. Further, tungsten has very high melting point `(3300 K)` and as such the filament will not burn at the high temperature `(2400 K)` at which it becomes incandescent.
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Knowledge Check

  • The metal used in incandescent lamps is

    A
    Mo
    B
    Pt
    C
    W
    D
    Cr

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    D
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  • The filament of an electric bulb is made of

    A
    iron
    B
    michrome
    C
    tungsten
    D
    graphite

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