1. At 0°C a steel cable is 1km long and 1cm diameter when it is heated it expands and its resistivity increases. Calculate the change in resistance of the cable as it is heated from 0-20°C The temperature coefficient of resistance a, gives the fractional increase in resistance per °C. So increase in resistance AR = Ra.AT Where R, is the resistance at 0°C For steel a, 0.003 °C The coefficient of linear expansion a- gives the fractional increase in length per °C temperature rise. So increase in Length AL La-AT Where L, is the length at 0°C For steel a₁ = 12 x 10 °C-1 The resistivity of steel at 0°C = 1.2 x 10 Qm

1. At 0°C a steel cable is 1km long and 1cm diameter when it is heated it expands and its resistivity increases. Calculate the change in resistance of the cable as it is heated from 0-20°C The temperature coefficient of resistance a, gives the fractional increase in resistance per °C. So increase in resistance AR = Ra.AT Where R, is the resistance at 0°C For steel a, 0.003 °C The coefficient of linear expansion a- gives the fractional increase in length per °C temperature rise. So increase in Length AL La-AT Where L, is the length at 0°C For steel a₁ = 12 x 10 °C-1 The resistivity of steel at 0°C = 1.2 x 10 Qm

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 27.5CQ: How does the resistance for copper and for silicon change with temperature? Why are the behaviors of...

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Similar questions

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