(a) Assume the spatial distribution of the current on a very thin centerfed half-wave dipole lying along the z-axis to be { I }_{ 0 }\cos { 2\pi z } . Find the charge distribution on the dipole. What is the wavelength? (b) Repeat part (a), assuming the current distribution along the dipole to be a triangular function described by
I\left( z \right) ={ I }_{ 0 }\left( 1-4\left| Z \right| \right)