3. For carbon; P20°c = 3.5 x 10-50-m and a = -5.0 x 10-4/°C. a) At what temperature does a carbon resistor have a resistance of 995 , if it has resistance of 1000 at 20°C? Assume negligible thermal expansion/contraction. b) What is the conductivity of carbon at the new temperature? c) How does a negative temperature coefficient of resistivity affect the conductivity of a material?

3. For carbon; P20°c = 3.5 x 10-50-m and a = -5.0 x 10-4/°C. a) At what temperature does a carbon resistor have a resistance of 995 , if it has resistance of 1000 at 20°C? Assume negligible thermal expansion/contraction. b) What is the conductivity of carbon at the new temperature? c) How does a negative temperature coefficient of resistivity affect the conductivity of a material?

Physics for Scientists and Engineers, Technology Update (No access codes included)

9th Edition

ISBN:9781305116399

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter27: Current And Resistance

Section: Chapter Questions

Problem 27.75AP: Review. When a straight wire is warmed, its resistance is given by R = R0,[1 + a(T T0)] according...

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