Q1-In hugyen's principle of wave theory why the waves are move in forward direction not in backward direction means they move forward as a new source why not in backward direction?
Ans- I think that waves move in forward direction sir i know that only so please give me a perfect answer with proof if any
Negative wavelets.
The original Huygens Principle does not clearly account for the wave direction. The important point is that the wavelet phase must be considered. However, the diagram below shows that additional negative wavelets easily solve this problem. The use of black and white wavelets proves to be preferable.
Regular traveling waves cannot travel backward.
The wavelets are well separated forward but they cancel backward.
THIS IS FROM:
http://www.rhythmodynamics.com/Gabriel_LaFreniere/sa_Huygens.htm
Huygens' principle is a fundamental concept in wave theory that helps us understand the propagation of waves. According to Huygens' principle, every point on a wavefront acts as a source of secondary spherical wavelets. These secondary wavelets combine to form the new wavefront, and the process continues.
The reason why the waves move in the forward direction rather than backward is due to the constructive interference of these secondary wavelets. When these wavelets combine, they reinforce each other in the forward direction, creating a coherent wavefront that propagates forward.
To see why waves do not propagate backward, let's consider the scenario where waves move in the backward direction. In this case, the secondary wavelets would be generated in the backward direction. However, when we consider the spherical geometry of these wavelets, we observe that they would interfere destructively with waves generated at other points on the wavefront. As a result, the backward-propagating waves would cancel each other out, preventing any net propagation in that direction.
To further illustrate this, imagine a pebble dropped into a still pond. The initial circular wavefront generated by the pebble can be considered as the source of secondary wavelets. These wavelets combine and propagate outward, creating a ripple effect. If we were to try and reverse this process and imagine waves coming from all points on the circular ripple, we would find that these secondary wavelets cancel each other out, leading to a net motionless state.
Therefore, while Huygens' principle allows us to visualize the propagation of waves, it also suggests that waves preferentially move in the forward direction where constructive interference occurs. This phenomenon is supported by numerous experimental observations and forms the basis of our understanding of wave behavior.