An electric field of 1139 v/m is applied to a section of silver of uniform cross section. find the resulting current density if the specimen is at a temperature of 3 ◦c . the resistivity ρ of silver is 1.59 × 10−8 ω · m at 20 ◦c . and its temperature coefficient is 0.0038 (◦c)−1 . answer in units of a/m

So, you're going to need the equation ρ = ρo [1 + α(T-To)]  

1.59x10^-8 ohms*m is your ρo because that is measured at your reference temperature (To), 20◦C. T is your 6◦C and α is 0.0038(◦C)−1. So, using that you solve for ρ. If you keep up with the units though, you notice it comes out to be ohms*m and that isn't what you want.  

So, the next equation you need is J=σE where E is your electric field (3026 V/m) and σ is the electrical conductivity which is the inverse of your answer you got in the previous equation. So find the inverse of that answer and multiply it by your electric field and that will give you the current density.  

I hope this helps!

Explanation:

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