An extremely long coaxial cable includes a solid cylindrical inner conductor of radius 4mm, surrounded by the outer cylindrical conductor having inner radius 7mm, and outer radius 9.5mm . The region among the two conductors is filled with a waxlike insulating material to keep the conductors from touching one other. The inner conductor carries a current 2.55A, into the page, whereas the outer conductor carries a current 2.05A , out of the page.
A) Employ Ampère's law to deduce an expression for the magnetic field as a function of r (the distance from the central axis) at points among the two conductors (R1
B) Utilize Ampère's law to deduce an expression for the magnetic field as a function of r (the distance from the central axis) at points within the outer conductor (R2i
C) Utilize Ampère's law to deduce an expression for the magnetic field as a function of r (the distance from the central axis) at points exterior to the outer conductor (r>R2o ). Employ this expression to find out the magnetic field at 14.9 mm .