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 sphere of radius R has a charge density sigma . The electric intensity at a point at a distance r from its centre is

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

A long cylidrical conductor of radius R carries a current i as shown in figure. The current desity J is a function of radius according to J=br , where b is a constant. Find an expression for the magnetic field B a. at a distasnce r_1ltR and b.at a distance r_2gtR, measured from the axis.

A circular coil of radius R carries a current i . The magnetic field at its centre is B . The distance from the centre on the axis of the coil where the magnetic field will be B//8 is

A long cylindrical conductor of radius R carries I as shown. The current density is a function of radius r as j = br, where b is a constant. The magnetic field at a distance r_(1)(r_(1)ltR) is

A cylindrical metal rod of radius "R" carries a current l .The velocity of free electrons drifting at a distance r(

An infinitely long cylinderical wire of radius R is carrying a current with current density j=alphar^(3) (where alpha is constant and r is the distance from the axis of the wire). If the magnetic fixed at r=(R)/(2) is B_(1) and at r=2R is B_(2) then the ratio (B_(2))/(B_(1)) is