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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_____________.

a. length.b. cross-sectional area.c. resistivity.d. amount of electric current passing through them

Respuesta :

Answer:

length, cross-sectional area, and the amount of electric current passing through them

Explanation:

cjrodriguez89

Answer:

a) length b) cross-sectional area

Explanation:

  • The resistance of a wire, assumed to be an homogeneous one, of a resistivity ρ, length L and cross-sectional area A, is given by the following expression:

       [tex]R = \rho * \frac{L}{A}[/tex]

  • At the same time, the current flowing through the resistor, is related to the voltage applied at the ends of the wire, by Ohm's Law, as follows:

       [tex]I = \frac{V}{R}[/tex]

  • So, for a given voltage, the current is proportional to the voltage, being the proportionality constant the resistance of the resistor.
  • So, if the material of both resistances is the same, the wires can differ in the length L and / or in the cross-sectional area A.

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