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Resistance between two points on a conducting surface

Suppose we have a cylindrical resistor, with resistance given by $R=\rho\cdot l/(\pi r^2)$

Let $d$ be the distance between two points in the interior of the resistor and let $r\gg d\gg l$. Ie. it is approximately a 2D-surface (a rather thin disk).

What is the resistance between these two points?

Let $r,l\gg d$, (ie a 3D volume), is the resistance $0$ ?


Update:
An alternate exposition of the problem goes as follows:
A voltage difference is applied between two points a distance d apart, inside a material with resistivity $\rho$, and the current is measured, the proportionality constant V/I is called R. The material is a cylinder of height $l$ and radius $r$, and the two points are situated close to the center, we can write R as a function of $l$, $r$ and $d$, $R(l,r,d)$, for small $d$.

The questions are then:
What is (lim r->inf (lim l->inf ($R(l,r,d)$)))?
What is (lim r->inf (lim l->0 ($R(l,r,d)$)))?

TROLLHUNTER
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