Question

At the same temperature, two wires made of pure copper have different resistances. The same voltage is applied at the ends of each wire. The wires may differ in Check all that apply. View Available Hint(s) Check all that apply.(A) length.(B) cross-sectional area.(C) resistivity.(D) amount of electric current passing through them.

Answer 1

Answer:

A and B true, C and D false.

Explanation:

We only know that they have the same resistance and the same voltage is applied to them. We need to remember the formula of resistance of a wire:

$R=\rho \frac{L}{A}$

Where $\rho$ is the resistivity (a property of the material), L its length and A its cross-sectional area. We could change L and A and still obtain the same R. From this we see that:

A) True. They could have any length.

B) True. They could have any cross-sectional area.

C) False. Resistivity is a property of the material, in this case, copper.

D) False. I=V/R, and both are the same for both wires.

Answer 2

Answer:

(A) length.(B) cross-sectional area.

Explanation:

The two options that they could have different are the length and the cross sectional area, and that can make the have the different resitances the longer the wire the more resitance it will have, since they are made from the same material and the same voltage is applied ot them, neither C or D could be because the resistivity depends solely on the material with which things are made of and both are pure copper wires.