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The resistivity of ‘X’ decreases with temperature and its coefficient of resistivity is negative. Identify X.

The resistivity of ‘X’ decreases with temperature and its coefficient of resistivity is negative. Identify X. Correct Answer Silicon

The coefficient of resistivity is negative for semiconductors and their resistivity decreases with temperature. The relaxation time does not change with temperature but the number density of free electrons increases exponentially with the increase in temperature. Consequently, the resistivity decreases exponentially with the increase in temperature.

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