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## Homework Statement

In the figure below, current is set up through a truncated right circular cone of resistivity 898 Ω·m, left radius a = 2.00 mm, right radius b = 2.30 mm, and length L = 1.64 cm. Assume that the current density is uniform across any cross section taken perpendicular to the length. What is the resistance of the cone?

HINT: Consider a cross-sectional slice of thickness dx. How is the resistance of that slice related to the resistivity of the material? How do you relate the resistance of the slice to the distance x from the left end and the full distance L?

## Homework Equations

R = ρ * (L/A)

## The Attempt at a Solution

Okay so I haven't gotten very far with this one. I know you have to set up an integral with respect to L, so I tried an integral from 0 to 0.0164 m and I related the radius as (b-a / L) * dx + 2

^{2}) So I had an integral of [itex]\int\frac{ρx dx}{\pi* ((\frac{b-a}{L} * x) + 2)^{2}}[/itex] but I had a really hard time trying to work this out. Can someone just set me off in the right direction?