In the figure shown, consider a long hollow cylindrical metal pipe of inner radius a and outer radius b in which flows a current I uniformly distributed over the cross section of the conductor. I In order to calculate the magnetic field at a point P a distance R from the axis, where a < r < b i.e., P is within the metal, we carry out a line integral along a path which encloses all the current im the conductor. we evaluate a line integral along a path that passes through the point P. we evaluate Bd, where di is directed along the direction of current flow. it would be easiest to use the Biot Savart Law.

In the figure shown, consider a long hollow cylindrical metal pipe of inner radius a and outer radius b in which flows a current I uniformly distributed over the cross section of the conductor. I In order to calculate the magnetic field at a point P a distance R from the axis, where a < r < b i.e., P is within the metal, we carry out a line integral along a path which encloses all the current im the conductor. we evaluate a line integral along a path that passes through the point P. we evaluate Bd, where di is directed along the direction of current flow. it would be easiest to use the Biot Savart Law.