The current density varies radical distance r as `J=ar^(2)`, in a cylindrical wire of radius R. The current passing through the wire between radical distance `R//3 and R//2` is,

A cylindrical wire if radius R = 2 mm is of uniform area of cross-section. The current density through a cross-section varies with radial distance r as J = ar^(2) , where a =3.2 xx 10^(11)A//m^(2) and r is in metres. What is the current through the outer portion of the wire between radial distances R//2 and R?

The current density bar(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 = (J_(0) r)/(a) , where J_(0) = (10^(5))/(4 pi) A//m^(2) . Find the magnitude of the magnetic field at r = (a)/(2) in mu T

A long cylindrical conductor of radius R carries a current i as shown in the figure. The current density J varies across the cross-section as J = kr^(2) , where, k is a constant. Find an expression for the magnetic field B at a distance r (lt R) from the axis

The current density across a cylindrical conductor of radius R varies in magnitude according to the equation J = J_0(1 - (r )/(R )) where r is the distance from the central axis. Thus, the current density is a maximum J_0 at that axis (r = 0) and decreases linearly to zero at the surface (r = R). Calculate the current in terms of J_0 and the conductor 's cross - sectional area A = piR^2 .

A non-homogeneous cylinder of radius "R" carries a current I whose current density varies with the radial "distance "r" from the centre of the rod as J=sigma r where sigma is a constant.The magnetic field at a point "P" at a distance r

A:Current density is a very is a vector quantity . R : Electric current , passing through a given unit area is current density.