We have 5x10¹6 doubly charged positive ions (q=2e) per m³, all moving west with a speed 105 m/s. In the same region there are 10¹7 electrons per m³ moving northeast with a speed 106 m/s. What are the magnitude and direction of the current density ?

We have 5x10¹6 doubly charged positive ions (q=2e) per m³, all moving west with a speed 105 m/s. In the same region there are 10¹7 electrons per m³ moving northeast with a speed 106 m/s. What are the magnitude and direction of the current density ?

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter9: Current And Resistance

Section: Chapter Questions

Problem 28P: An aluminum wire 1.628 mm in diameter (14-gauge) carries a current of 3.00 amps, (a) What is the...

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Concept explainers

Microscopic view of current

In physics, the term current is expressed as the rate of flow of electric charges across the area per unit time (I=q/t). It propagates along in the direction of the motion of positive charges. When the current is caused by the motion of electrons, the direction of the current is opposite to the flow.

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We have 5x10¹6 doubly charged positive ions (q=2e) per m³, all moving west with a speed
10³ m/s. In the same region there are 10¹7 electrons per m³ moving northeast with a speed 106
m/s. What are the magnitude and direction of the current density j?

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