Resistance in metals increases with increasing temperature according to the equation, ρ(T) = ρo(1 + α(T - To)) where α is the temperature coefficient of resistivity and ρo is the resistivity at temperature To. For a particular wire α = 9.5 × 10-3 1/°C and the resistivity is ρo = 4.5 × 10-7 Ω⋅m at To = 154 °C. a). Input an expression for the temperature T2 at which the resistance of a wire will be twice as high as at T0. b). If the wire is L = 1 m long with a radius of r = 1 cm, what is its resistance R, in Ω, at 2To?

Resistance in metals increases with increasing temperature according to the equation, ρ(T) = ρo(1 + α(T - To)) where α is the temperature coefficient of resistivity and ρo is the resistivity at temperature To. For a particular wire α = 9.5 × 10-3 1/°C and the resistivity is ρo = 4.5 × 10-7 Ω⋅m at To = 154 °C. a). Input an expression for the temperature T2 at which the resistance of a wire will be twice as high as at T0. b). If the wire is L = 1 m long with a radius of r = 1 cm, what is its resistance R, in Ω, at 2To?

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter9: Current And Resistance

Section: Chapter Questions

Problem 70AP: A 10.00-meter long wire cable that is made of copper has a resistance of 0.051 ohms, (a) What is the...

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