Diffraction Pattern

[Junwei Sun 4I]

Could someone please explain what are constructive interference and destructive interference? Thanks.

[Junwei Sun 4I]

More specifically what does "in phase" and "out of phase" mean?

[VPatankar_2L]

Constructive interference refers to waves that are in phase. This means that you can add them to give rise to a larger wave. Destructive interference refers to waves that are out of phase, which means that you can subtract the waves' peaks. If both waves are at their highest peak at a given moment, they are considered to be in-phase. If one wave is at its highest peak (positive) while the other wave is at its lowest peak (negative), at a given moment, they are out of phase.

[Lindsey Chheng 1E]

Could someone please explain what are constructive interference and destructive interference? Thanks.

In phase means to interact with

Constructive
-two wavelengths are in phase, that is the peak of one wave is in phase with the peak of the other wave
-together, the two waves result in a larger wave

Destructive Interference
-two waves are out of phase, that is the peak of one wave interacts with the trough (lowest part of the wave) of the other wave
-together, the two waves result in a smaller wave