To develop this problem it is necessary to have the concepts related to Ohm's law and resistivity.
Ohm's law is defined by the equation
[tex]V= RI[/tex]
Where
R=Resistence
I = current
V= Voltage
While the resistivity equation is given by
[tex]\rho= R*\frac{A}{L}[/tex]
Where
[tex]\rho=[/tex] resistivity
A= cross-section area
R= Resistance
L=Lenght of wire
A) We can find the resistence re-arranging our first equation, so
[tex]R= \frac{V}{I}[/tex]
[tex]R= \frac{120V}{9.85A}[/tex]
[tex]R= 12.18\Omega[/tex]
B) From our second equation we can re-arrange for L, so
[tex]\rho= R*\frac{A}{L}[/tex]
[tex]L=\frac{R\pi r^2}{\rho}[/tex]
[tex]L = \frac{(12.18)(3.70*10^{-3})^2(\pi)}{1.5*10^{-6}}[/tex]
[tex]L=349.34m[/tex]
