Calculating current in parallel wire

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djaziria
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Homework Statement



A vertical straight wire carrying an upward 14.9A current exerts an attractive force per unit length of 8.50×10-4N/m on a second parallel wire 6.20cm away. What is the magnitude of the current that flows in the second wire?

Homework Equations



I2=2pir*F/I1*4pi e-7

The Attempt at a Solution



I2=2pi(.062)*8.5e-4/14.9*4pi e-7
I2=2.7926e-11

I keep getting ridiculous numbers and I can't figure out what I'm doing wrong...help?!
 
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I think you got your equation slightly off.
Starting with F/[itex]\Delta[/itex]L=[itex]\mu[/itex]0I1I2/2pi*r, I ended up with
I2=(F/[itex]\Delta[/itex]L)(2pi*r/[itex]\mu[/itex]0I1).
 
Check your own arithmetic. The exponents indicate you screwed up the division.

Do the basic checks before running for help.