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Question
As the temperature of a metallic resistor is increased, the product of its resistivity and conductivity ____________ .
Options
increases
decreases
remains constant
may increase or decrease
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Solution
As the temperature of a metallic resistor is increased, the product of its resistivity and conductivity remains constant.
Resistivity = `1/"conductivity"`
The product of resistivity and conductivity is equal to a constant.
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