Electric Field in a Wire (Concepts)

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Homework Statement



A) [Directly proportional/Inversely proportional] The electric field inside the wire is ... to resistivity of the material the wire made of.

B) [Directly proportional/Inversely proportional] The electric field inside the wire is ... to the current passing through the wire.

Homework Equations


This is my problem, I can't seem to find any equations that relate electric field to the resistivity or current in the wire.

The Attempt at a Solution


My guess is that A is inversely proportional, and B is directly proportional but its just a guess.
 
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Ohm's Law comes in two forms. The form more common to intro physics is:

[tex]V=IR[/tex]

The other form is the following:

[tex]J=\sigma E[/tex] where J is the current density and sigma is the conductivity (inverse of resistivity).

Can you use these equations to answer the questions?
 
Thanks GO1! Thats exactly what i was looking for. I've got the answers now :)