Induced Voltage on Parallel Phone Line

[sandy.bridge]

Homework Statement

If we know the orientation of a power line that is parallel to a telephone line, how can we determine the voltage induced on the telephone line without knowing the radius' of the lines? We are told the power line is at 200A at 60-Hz, we know how far each of the lines are from each other, but we do not know the radius of each of the lines.

 

[.Scott]

Since we're assuming that there is no resistance in these lines, the radius of the copper should be treated as zero.
Apparently there is no load on the phone line.

 

[rude man]

The telephone and power wires are most probably twisted pairs. That means that (a) there is very little B field escaping the power line, and (b) there is very little area between the telephone wires to pick up an emf.