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Calculate the resistance of an aluminium...

Calculate the resistance of an aluminium wire of length 50 cmand cross sectional area `2.0mm^(2)`. The resistivity of aluminium is `(rho)=2.6xx10^(-8)(Omega)m.`

Text Solution

Verified by Experts

The resistance is R `=rho(l)/(A)`
`=((2.6xx10^(-8)Omega-m)xx(0.50m))/(2xx10^(-6)m^(2))=0.0065Omega`
We arrived at Ohm's law by making several assumptions about the existence and behaviour of the free electrons . These assumption are not valid for semiconductors , insulators , solutions etc . Ohm 's law cannot be applied in such cases.
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