This one is about the difference between constructive and destructive waves.
First, some background knowledge: When two or more waves interact with each other at the same time, a new, combined wave is created. This interaction is known as wave interference and there are two types of wave interference.
1. Constructive Interference.
This is when the interacting waves coming together are moving in the same direction (when one wave upwards, the other waves upwards as well). The combination of these two waves will strengthen each other and produce a wave that adds the intensity of the combined waves. (e.g if one wave moves up one centimeter and the other wave moves up one centimeter, the combined wave will move up two centimeters)
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| Constructive Interference |
This is when the interacting waves that are coming together are moving in a different direction (when one wave moves upwards, the other moves downwards). This combination will interfer with each other destructively. The intensity of the combined wave is lowered and the amplitude is shortened in length. (They subtract)
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| Destructive Interference |
