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प्रश्न
A metallic wire has a resistance of 3.0 Ω at 0°C and 4.8 Ω at 150°C. Find the temperature coefficient of resistance of its material.
उत्तर
Here, R0 = 30 Ω , Rt = 4.8 Ω , t = 150° C , α = ?, where α is the temperature coefficient of resistance.
We know that
Rt = R (1 + αt)
α = `("R"_"t" - "R"_0)/("R"_0 xx "t")`
`= (4.8 - 3.0)/(3xx150)`
`= 1.8/(3xx150)`
= 4 × 10-3° C-1
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