Q.7- A parallel-plate capacitor with circular plates of radius R and separated by a distance h is charged through a straight wire carrying current I, as shown in the Figure R a) Show that as the capacitor is being charged, the Poynting vector S points radially inward toward the center of the capacitor. b) by integrating S over the cylindrical boundary, show that the rate at which energy enters the capacitor is equal to the rate at which electrostatic energy is being stored in the electric field.