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Question
Pieces of copper and of silicon are initially at room temperature. Both are heated to temperature T. The conductivity of ______.
Options
both increases.
both decreases.
copper increases and silicon decreases.
copper decreases and silicon increases.
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Solution
Pieces of copper and of silicon are initially at room temperature. Both are heated to temperature T. The conductivity of copper decreases and silicon increases.
Explanation:
The resistance of copper wire increases with temperature, which causes a drop in conductivity, while the resistance of silicon wire reduces with temperature, which causes an increase in conductivity.
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