Question

Compute the voltage drop along a 26-m length of household no. 14 copper wire (used in 15-A circuits). The wire has diameter 1.628 mm and carries a 13-A current. The resistivity of copper is 1.68×10−8Ω⋅m. Express your answer to two significant figures and include the appropriate units

Answer 1

Answer:

V= 2.7 [v]

Explanation:

The value of the resistance is given by:

$R=L*\frac{Rho}{A}\\\\where:\\R=resistance\\L=Lenght\\Rho=Resistivity\\A=Transversal -Area$

so:

$R=26m*\frac{(1.68*10^{-8}ohm*m)}{\pi *(\frac{1.628*10^{-3}m}{2})^2}\\R=0.21 Ohm$

We can calulate the voltage dropped using the Ohm's law:

$V=I*R\\V=13A*0.21Ohm=2.7V$