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## Homework Statement

Suppose that you wish to fabricate a uniform wire out of 0.900 g of copper. If the wire is to have a resistance R = 0.700 ohm, and if all of the copper is to be used.

(a) What will be the length of the wire? M

## Homework Equations

R = pL/A

R = .700 ohm and p = 1.7 x 10^-8

## The Attempt at a Solution

first thing i did was input the given number

.700 = (1.7x10^-8)L/A

my main problem is finding A with the given weight of copper, but this is what i did.

n = m/M = .900/63.54 = .0142 then,

.0142(6.02x10^23) = 8.53 x 10^21

this is where i get lost because to get A its A = DeltaQ/DeltaT but time was never a given and i believe its not needed.

(8.53 x 10^21) x (1.6 x 10^-19) = 1364.8

I know there are other ways to get "A" by A = DeltaV/R but Volts were never given.

Any help on this would be great.