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A metallic sphere of radius R and specific resistance ρ is taken and two wires( negligible resistance) connected to it at random positions (say at an angle θ apart from each other.both the wires are perpendicular to the surface of the metallic sphere. Prove that the Magnetic field B at the centre O is zero when a current I is turned on in the circuit.

This situation is kind of like -

imagine a hollow pendulum . now its connected to one thread(suppose its a wire.) ...we connect another wire to this pendulum at a random position. and using a cell create a potential difference between the two ends of the wires such that a current flows through the wires, into the sphere ...all around the sphere and back to the other wire

What I did is assume to the sphere to be made of two different resistors connected in parallel. one piece subtends a solid angle dΩ at the centre and hence the other piece will subtend an angle 4∏- dΩ.

After that ...I have no clue.

This situation is kind of like -

imagine a hollow pendulum . now its connected to one thread(suppose its a wire.) ...we connect another wire to this pendulum at a random position. and using a cell create a potential difference between the two ends of the wires such that a current flows through the wires, into the sphere ...all around the sphere and back to the other wire

What I did is assume to the sphere to be made of two different resistors connected in parallel. one piece subtends a solid angle dΩ at the centre and hence the other piece will subtend an angle 4∏- dΩ.

After that ...I have no clue.

## Homework Statement

## Homework Equations

## The Attempt at a Solution

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