A long cylindrical conductor of radius R carries a current I as shown in figure. The current density J is a function of radius according to , j = br , where b is a constant. Find an expression for the magnetic field B.

A cylindrical conductor of radius R is carrying a constant current. The plot of the magnitude of the magnetic field. B with the distance d from the center of the conductor, is correctly represented by the figure

Figure shows a cross section of a long cylindrical conductor of radius a containing a long cylindrical hole of radius a containing a long cylindrical hole of radius b. THe central axes of the cylinder and hole are parallel and are distance d apart, current i is uniformly distributed over the tined area. what is the magnitude of the magnetic field at the centre of the hole ?

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The current density J inside a long, solid cylindrical wire of radius a=12 mm is in the direction of the central axis, and its magnitude varies linearly with radial distance r from the axis according to J=J0 ra, where J0= 1054 π A/m^2. Find the magnitude of the magnetic field at r = a/2 in μT