How Far from a Conductor Is a Magnetic Field of 3.1x10^-5T?

Thread starter jalen
Start date Mar 23, 2008
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Conduction Fields Magnetic Magnetic fields

AI Thread Summary

To determine the distance from a conductor where the magnetic field strength is 3.1x10^-5T, the formula B = μI/(2πr) is used. Rearranging this gives r = μI/(2πB). Substituting the values, including the current of 12.5A, leads to an incorrect calculation of r as 8.1x10^5m due to an error in using the permeability constant. The correct value for the permeability of free space should be used to find the accurate distance. The discussion highlights the importance of using the correct constants in magnetic field calculations.

Mar 23, 2008

jalen

Homework Statement

12.5A, 3.1x10^-5

Homework Equations

How far from a long conductor passing a current of 12.5A is the magentic field of strength 3.1x10^-5T?

The Attempt at a Solution

B= uI/2(pi)r

r=uI/2(pi)B
=(4pi)(12.5A)/ 2(pi)(3.1x10^-5T)
= 8.1x10^5m

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Mar 23, 2008

Snazzy

u_0 isn't 4 pi.

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