For an experiment I am conducting in a grade 11 physics course, I am attempting to find the effects of resistivity on current density. To ensure accurate results, I attached, in seperate trials, the maximum length possible of 5 different types of wire (with varying material composition but constant thickness) to a circuit which could measure resultant voltage drop/gain and current. As I used different lengths of wire for each trial there is the additon of an unwanted length variable, which to control, must be normalised. In doing this, I calculated the normalised resistance of each wire, assuming a constant length and thickness for the wire, with only resistivity varying. In order to calculate current density, the current through the circuit is required, which, along with voltage, would have been affected when resistance was normalized. Is there any way to calculate normalised current when only normalised resistance has been determined? Thanks.