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**1. Homework Statement**

A cable with given diameter D1 is given, a small hole with diameter D2 is drilled on it. The axis of them are parallel and the distance between the axis are given as r. There is a uniform steady current density flowing through it. How to calculate the magnetic field at the center of cable and center of the hole?

I have problem on how to start with the question. I am not sure which point the magnetic field is pointing and also, if i use ampere's law, i m using the closed path including outside. Thinking of Using Biot Savart law, but still i m having trouble in figuring out the direction of magnetic field.

Thanks