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Question
Solve the following problem.
A silver wire has a resistance of 4.2 Ω at 27° C and resistance 5.4 Ω at 100° C. Determine the temperature coefficient of resistance.
Solution
Given: R1 = 4.2 Ω, R2 = 5.4 Ω, T1 = 27° C, T2 = 100° C
To find: Temperature coefficient of resistance (α)
Formula: α = `("R"_2-"R"_1)/("R"_1("T"_2-"T"_1))`
Calculation: From the formula,
α = `(5.4-4.2)/(4.2(100-27))` = 3.91 × 10−3/° C
The temperature coefficient of resistance is 3.91 × 10−3/° C.
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