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Good Conductor |
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A medium is called Good Conductor when  |
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The propagation constant in this case can be written as |
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Since,  =  = =  =  , we get |
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giving |
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Since  a good conductor behaves more like a Lossy Transmission Line. |
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Since the wave amplitude varies as  the wave amplitude reduces to  of its initial value over a distance
of  . This distance is called 'Skin Depth' or 'Depth of Penetration'
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We therefore have the Skin Depth |
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A wave effectively penetrates a distance equal to the skin depth in a Good Conductor. |
Material |
Conductivity |
Skin Depth |
Silver |
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Copper |
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Aluminium |
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Doped Silicon |
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Earth |
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Since the depth of penetration is of the order of micrometer in good conductor the word skin depth is quite justified
for the effective depth of penetration |
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Skin depth decreases with increase in both the frequency and the conductivity. |
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