The instructions for an electric lawn mower suggest that a 20-gauge extension cord can be used for distances up to 35 m, but a thicker 16-gauge cord should be used for longer distances, to keep the resistance of the wire as small as possible. The cross-sectional area of 20-gauge wire is 5.2 × 10 -7 m², while that of 16-gauge wire is 13 × 10 -7 m². Determine the resistance of: (a) 35 m of 20-gauge copper wire and

The instructions for an electric lawn mower suggest that a 20-gauge extension cord can be used for distances up to 35 m, but a thicker 16-gauge cord should be used for longer distances, to keep the resistance of the wire as small as possible. The cross-sectional area of 20-gauge wire is 5.2 × 10 -7 m², while that of 16-gauge wire is 13 × 10 -7 m². Determine the resistance of: (a) 35 m of 20-gauge copper wire and

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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