Two long, straight copper pipes, each of radius a, are held a distance 2d apart (see Fig...

Two long, straight copper pipes, each of radius a, are held a distance 2d apart (see Fig. 7.50). One is at potential V₀, the other at −V₀. The space surrounding the pipes is filled with weakly conducting material of conductivity σ. Find the current per unit length that flows from one pipe to the other. [Hint: Refer to Prob. 3.12.]

Figure 7.50

Reference prob 3.12

Two long, straight copper pipes, each of radius R, are held a distance 2d apart. One is at potential V₀, the other at −V₀ (Fig. 3.16). Find the potential everywhere. [Hint: Exploit the result of Prob. 2.52.]