Number 10 copper wire (radius = 1.3 mm)is commonly used for electrical installations in homes.What is the voltage drop in 40 m of #10 copper wire if it carries a current of 10 A? (The resistivity of copper is 1.7 x 10^-8 W*m. ) A)1.3 V B)0.77 V C)0.50 V D)0.13 V

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Quizplus · Accepted Answer

The voltage drop is given by V = IR, where I is the current and R is the resistance. The resistance of a wire is given by R = ρL/A, where ρ is the resistivity, L is the length, and A is the cross-sectional area. The cross-sectional area of a wire is given by A = πr^2, where r is the radius. Substituting these equations into the first equation, we get V = IρL/(πr^2). Plugging in the given values, we get V = (10 A)(1.7 x 10^-8 Ωm)(40 m)/(π(1.3 mm)^2) = 1.3 V.

Number 10 Copper Wire (Radius = 1