Calculating Resistivity: Finding the Area of a Wire

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To calculate the resistivity of a wire with a diameter of 1.51 mm and a length of 32.7 m, the resistance is given as 1.5 ohms. The formula R = ρL/A is used, where R is resistance, ρ is resistivity, L is length, and A is the cross-sectional area. The area A can be calculated using the formula A = πr^2, with the radius r being half the diameter. After determining A, it can be plugged into the equation to find the resistivity ρ. The discussion focuses on solving for the area to complete the resistivity calculation.
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Homework Statement


A wire has a diameter of 1.51 mm and a length of 32.7 m, and is found to have a resistance of 1.5 capital omega. What is the resistivity of the wire?



Homework Equations





The Attempt at a Solution


R=qL/A
R=.0051/2=7.55E-4
L=32.7
A = ?
How do i find A to plug into the equation to find q?
 
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In the formula R = resistance of the wire, A, the area of the cross section of the wire = π*r^2, where r is the radius of the wire = diameter/2.
 

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