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14. Figure 10 shows a short section of a long cylindrical conductor of resistivity p and radius carrying a steady current Figure 10 (a) Show that the magnetic field B at the surface is given by B =mol/(2er) [3] (b) Redraw the diagram and show clearly the direction of the E and H vectors. [2] (c) Indicate the direction of the Poynting vector at the surface of the cylinder. [1] (d) Calculate the current density flowing through the material. [1] (e) Show that the flow of electromagnetic power per unit area across the curved surface is given by: pl [5] 21'r (f) Using the result obtained in question (e), show that the total power radiated by the cylinder is: pl ar? [4] (g) Show that this result is consistent with Ohm's law [4]