Pr3. A long, cylindrical wire has the cross-section of an annulus, i.e. region between two concentric circles, see the shaded area in figure a). The outer radius of the wire is 2R, the inner diameter is R. Current I flows along the wire (perpendicularly into the page) in uniform distribution between radii R and 2R. а) b) XI R XI R 2R 2R a) Find and plot the magnitude of the magnetic field as a function of distance r from the symmetry axis of the wire. b) Suppose now that the cavity of radius R is not coaxial with the outer surface of the wire, as seen in figure b). Find the magnetic field at point P located in the center of the cavity. The current distribution in the wire is assumed to be uniform, the value of current is I.

Pr3. A long, cylindrical wire has the cross-section of an annulus, i.e. region between two concentric circles, see the shaded area in figure a). The outer radius of the wire is 2R, the inner diameter is R. Current I flows along the wire (perpendicularly into the page) in uniform distribution between radii R and 2R. а) b) XI R XI R 2R 2R a) Find and plot the magnitude of the magnetic field as a function of distance r from the symmetry axis of the wire. b) Suppose now that the cavity of radius R is not coaxial with the outer surface of the wire, as seen in figure b). Find the magnetic field at point P located in the center of the cavity. The current distribution in the wire is assumed to be uniform, the value of current is I.