Reading assignment: PpP 8.1-8.3, 10.1-10.4
Which of the following is NOT true of the 3D "wave vector"?
Its magnitude is equal to 2π/λ.
For every point inside a plane wave, it points the same
every point inside a spherical wave, it
points the same direction.
It tells us which way the wave is going.
In 1D it reduces to the wave number k.