In fact, at all points the two waves exactly cancel each other out and there is no wave left! This is the single most amazing aspect of waves. When the first wave is down and the second is up, they again add to zero. Now what happens if we add these waves together? When the first wave is up, the second wave is down and the two add to zero. However, carefully consider the next situation, again where two waves with the same frequency are traveling in the same direction: You may be thinking that this is pretty obvious and natural – of course the sum of two waves will be bigger than each wave on its own. The waves are adding together to form a bigger wave. This situation, where the resultant wave is bigger than either of the two original, is called constructive interference. If we add these two waves together, point-by-point, we end up with a new wave that looks pretty much like the original waves but its amplitude is larger.
To start exploring the implications of the statement above, let’s consider two waves with the same frequency traveling in the same direction: As it turns out, when waves are at the same place at the same time, the amplitudes of the waves simply add together and this is really all we need to know! However, the consequences of this are profound and sometimes startling.
#Just into the waves how to
Thus, we need to know how to handle this situation. This is very different from solid objects.
In the last section we discussed the fact that waves can move through each other, which means that they can be in the same place at the same time. Constructive and Destructive Interferenceĥ.2 Constructive and Destructive Interference