Visualization and interpretation for the electromagnetic derivation of Snell's laws

Veritable snapshots-in-time of the vector fields in the classic problem of plane wave refraction at a planar interface are drawn simply and directly u sing a contour-plotting routine. These field pictures, together with the an tecedent mathematics, give students and teachers a panoramic view of the pe rtinent wave physics. Classroom examples and computer assignments, based on the methodology of this paper, help to underscore the real physical nature of our subject called electromagnetics.