Calculus 3 Lecture Notes, Section 11.5

for a plane wave traveling in an arbitrary direction with an expression when put equal to a constant (βz = constant), that will result in equiphase surfaces. The equation of an equiphase plane is given by . The radial vector (r) from the origin to any point on the plane, and β is the vector normal to the plane is shown in Figure (6.1). ................
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