Estimate its capacitance to earth

AI Thread Summary
To estimate the capacitance of a telephone wire suspended 10m above the ground, the mirroring method is recommended rather than the cylindrical capacitor formula, which yielded an incorrect answer. The discussion suggests considering two parallel wires with opposite charges to simplify the problem, maintaining the same electric field. Participants express confusion over the correct approach and seek clarification on applying the mirroring method effectively. The conversation highlights the importance of understanding different methods for calculating capacitance in this context. Overall, the mirroring method is emphasized as the appropriate technique for this scenario.
Ripperbat
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Homework Statement



A telephone wire of diameter 1mm is suspended 10m above the ground. Estimate its capacitance to Earth per unit length

Homework Equations





The Attempt at a Solution


I've tried to solve the problem by using the formula for a cylindrical capacitor and got the answer but apparently it was wrong. Instead it's supposed to be solved by the mirroing method. So now I'm lost. Help me please :)

Thx
 
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Ripperbat said:

Homework Statement



A telephone wire of diameter 1mm is suspended 10m above the ground. Estimate its capacitance to Earth per unit length

Homework Equations





The Attempt at a Solution


I've tried to solve the problem by using the formula for a cylindrical capacitor and got the answer but apparently it was wrong. Instead it's supposed to be solved by the mirroing method. So now I'm lost. Help me please :)

Thx


Consider two parallel 1mm thick wires a distance 20m apart with opposite charges, same electric field for the above problem. Does that make things easier? I'm not sure.
 

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