Along, straight wire with a circular cross section of radius r carries a current i. assume that the current density is not constant across the cross section of the wire, but rather varies as j=ar where a is a constant.
a) by the requirement that j integrated over the cross section of the wire gives the total current i, calculate the constant a in terms of i and r. express your answer in terms of the variables i, r, and appropriate constant
b) use ampere's law to calculate the magnetic field b(r) for r ? r. express your answers in terms of . (express your answer in terms of the variables i, r, r, and appropriate constants
c) use ampere's law to calculate the magnetic field b(r) for r ? r. express your answers in terms of i. express your answer in terms of the variables i, r, r, and appropriate constants