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

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter21: Current And Direct Current Circuits

Section21.2: Resistance And Ohm’s Law

Problem 21.3QQ: When does an incandescent lightbulb carry more current? (a) immediately after it is turned on and...

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