A long, hollow wire has inner radius R1 and outer radius R2. The wire carries current I uniformly distributed across the area of the wire.
a) Use Ampere's law to find an expression for the magnetic field strength in the region 0 Express your answer in terms of the variables R1, R2, r, I, and appropriate constants.
b) Use Ampere's law to find an expression for the magnetic field strength in the region R1 Express your answer in terms of the variables R1, R2, r, I, and appropriate constants.
c) Use Ampere's law to find an expression for the magnetic field strength in the region R2 Express your answer in terms of the variables R1, R2, r, I, and appropriate constants.
Just info given, no diagrams.
Obviously, the answer to A is 0, since no magnetic field exists in the center of the hollow wire, but I don't have a clue on where to begin for the equations to B and C.