What is the resistance of a copper wire 200 ft long and 0.016'' in diameter (T= 20°C)?

The resistance of the copper wire is 8.1 ohm.

Explanation:

Given:

     Length of the copper = 200 ft  

     Diameter of the copper = 0.016 inches

    Resistance of the copper=?

 Formula for Resistance is given as

     R = (ρL/A)

where,

    R- Resistance

    ρ- Resistivity of the given material

    L- Length of the material

    A- Area of the material

The solution is as follows:

       The resistivity of the copper at t=20°c is 10.37⁽CM*Ω⁾

        L= 200 ft

        D= 0.016"(inch to mils)

        1 inch= 1000 mils

therefore;

    0.016 inch = 16 mils

 A(cm)=(d mil)²

           = 256 cm

   R = (ρL/A) = ((10.37 200) / 256 )

                    = 8.1 Ω Or 8.1 ohm.