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Join Date: Jun 2008
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# how to caculate current density

06/11/2008 3:29 AM

how to calculate the current density of copper

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Guru

Join Date: Feb 2008
Location: Australia
Posts: 1746
#1

### Re: how to caculate current density

06/11/2008 5:32 AM

Fairly simple.

First, calculate the cross sectional area of the copper conductor. (You will need to calculate the total for each strand in the wire if it's not a solid wire or busbar)

Second, find out (measure) the current flowing through the copper conductor.

Finally divide the current by the cross sectional area and you will have a value in "Amps per square milimeter" (Or per square inch if you are in that other part of the world). That value is the current density in the conductor.

My University professor would insist that some of the terms above be a little more precise like "perpendicular cross section", but I don't think he's going to be looking at this site.

There are some other special conditions that happen at extremely high frequency where the current tends to flow in only the outside skin of the conductor, but I'm guessing from the question that this complication is probably not necessary to consider.

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Just an Engineer from the land down under.
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Join Date: Apr 2010
Posts: 1
#2

### Re: how to caculate current density

04/08/2010 2:27 PM

Metall Eng student, the reply by "just an engineer" seems simple, but what i want to know is when one is working with an electrolytic cell, my commen sence tells me that the area used to calculate the current density would be the surface area of the electrode...is this correct? i was given a question in an assignment, where the power density and current density of the "cell"( the cell is actually an ewlectric arc furnace but i am simplifying the question). There is also an work rate given in 430Kwh/ton. now one of the question are to calculate the electrode diameter.... to me it doesn't seem possible! the power density= 100Kw/meter squered of furnace area and current density= 3Amp/meter squered of electrode diameter. The electrode is carbon, and used to melt a copper concentrate at a rate of 1200 ton a day at an efficiency of 89%..............................please help!

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