# Can You Resist The Donut?

You are given a disk of thickness $$h$$ with inner and outer radii $$r_1$$ and $$r_2$$, respectively. If the resistivity of the disk varies as $$\rho = \rho_0 \left|\sec \varphi\right|$$, where $$\varphi$$ is the polar angle, find the resistance between the points $$A$$ and $$B$$.

Give your answer to 3 decimal places.

Details and Assumptions:

• The inner and outer rims are metal rings with zero resistance.
• Take $$\dfrac {r_2}{r_1} = e^2 \approx 7.389$$, $$\rho_0 = \SI{10}{\ohm \meter}$$, and $$h= \SI{3}{\centi \meter}$$.
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