3. Along an infinitely long, solid, straight conductor of radius a, an alternating current |= lo-cos(wt) [A] flows. Then the conductivity is limited and the frequency is low, the current can be assumed to be homogeneously distributed over the whole cross-section. Furthermore, the so- called quasi-stationary approximation can be used. This means that Ampere's law for magnetostatic fields can be used to calculate the magnetic field. I.e. the displacement current can be neglected. a) What is the direction of the electric field E outside b) Calculate the E and B fields inside the conductor. c) Calculate the electric field strength E(p,t) outside the conductor. Here p is the radial coordinate. Lead: use Stoke's theorem.

3. Along an infinitely long, solid, straight conductor of radius a, an alternating current |= lo-cos(wt) [A] flows. Then the conductivity is limited and the frequency is low, the current can be assumed to be homogeneously distributed over the whole cross-section. Furthermore, the so- called quasi-stationary approximation can be used. This means that Ampere's law for magnetostatic fields can be used to calculate the magnetic field. I.e. the displacement current can be neglected. a) What is the direction of the electric field E outside b) Calculate the E and B fields inside the conductor. c) Calculate the electric field strength E(p,t) outside the conductor. Here p is the radial coordinate. Lead: use Stoke's theorem.