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The question says: Suppose you wish to fabricate a uniform wire out of 1.00 g of copper. If the wire is to have a resistance of R=0.500 Ohm, and a density of d=8920 kg/m3, and if all the copper is to be used, what will be the:

a)length of the wire? >>ans. is 1.82 m

b) diameter of the wire? >>ans. is 0.28 mm

The equation is: R=p(rho)*l(length)/A(cross sectional area)

I found the area only, I'm lost!

But at least, based on the area, my diameter is supposed to be correct, but it wasn't!

I got 0.001>>lol

Anyways, I will show you what I did to find the area and the diameter:

First I found the volume of the wire: v=m(mass)/d(density)=0.001 kg/(8920 kg/m3)

and I got 1.12e(-7) m3

Then I found height, guess how!

R=p*l/A right?? ok, I canceled the length on top (numerator) with the length in the area equation: L*h and I was left with R=p/h, which means h=p/R=1.72e(-80) (rho or resistivity of copper, got it from our text book)/0.5= 3.44e(-8) m

Now I substituted both values in the formula: A=v/h=1.12e(-7)/3.44e(-8)=3.25 m2

Now I used it to find the diameter: d=A/pi=3.25/3.14(pi)= 0.001 mm

I know that there are several mistakes, so I'd like you all to help me improve my solution and also help me find the length. I'd really appreciate that!