Figure 4
From: Huygens' Principle geometric derivation and elimination of the wake and backward wave
(a–c) Source motion displacement for the forward wave: (a) the original forward wave front pulse compared with the additional forward wave front pulse due to the source motion. (b) The original forward wave front pulse which is the same as the wave front pulse from the stationary source. (c) The additional forward wave front pulse due to the source motion. (d–f) Source motion displacement for the backward wave: (d) the original backward wave front pulse compared with the additional backward wave front pulse due to the source motion. (e) The original backward wave front pulse which is the same as the wave front pulse from the stationary source. (f) The additional backward wave front pulse due to the source motion. (g–i) The original and additional wave fronts with v = c. (g) Forward and backward wave front pulses that would propagate from a stationary source. (h) Additional wave front pulses originating from source motion. (i) Forward wave front pulse created by the sum of the other two wave front pulses (g) and (h).
