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Question
A silver wire has a resistance of 2.1 Ω at 27.5°C, and a resistance of 2.7 Ω at 100°C. Determine the temperature coefficient of resistivity of silver.
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Solution
Given: Temperature, T1 = 27.5°C
Resistance of the silver wire at T1, R1 = 2.1 Ω
Temperature, T2 = 100°C
Resistance of the silver wire at T2, R2 = 2.7 Ω
Temperature coefficient of silver = α
Formula: It is related to temperature and resistance as,
α = `(R_2 - R_1)/(R_1(T_2 - T_1))`
= `(2.7 - 2.1)/(2.1(100 - 27.5))`
= `(2.7 - 2.1)/(2.1(72.5))`
= `0.6/152.25`
= 0.0039°C−1
Therefore, the temperature coefficient of silver is 0.0039°C−1.
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