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How resistivity of material depend on temperature. Write empirical formula . |
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Answer» Solution :`rArr` Resistivity or material depend on TEMPERATURE. Different material have different dependence on temperature. `rArr` Resistivity of metal increase with increase in temperature. `rArr` Resistivity of semiconductor decrease with increase in temperature. `rArr` Over a limited range of temperature that is not too LARGE the resistivity of METALLIC conductor is approximately given by. `rho_(T) = rho_(0) [1 + alpha (T - T_(0))] ` `rho_(T)` = resistivity at temperature T `rho_(0)` = resistivity at reference temperature `T_(0)` `alpha` = temperature coefficient of resistivity `rArr` Resistivity of same metals is given in table shown below. `rArr` For metals value of `alpha` is POSITIVE. `rArr` For semiconductor `alpha` is negative. ` rArr` For some metals value of `alpha` at `0 ""^(@) C` is shown in table below. 
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