What are the conditions for constructive and destructive interference?
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Solution
Constructive interference:
A single amplitude equal to the total of the amplitudes of the individual waves is produced by the interference of two or more waves of equal frequency and phase.
Constructive interference is another name for this kind of interference. Any position along the medium where the two interfering waves have a displacement in the same direction will experience constructive interference.
Because both waves in this instance have an upward displacement, the upward displacement of the medium is higher than the displacement of the two interfering pulses. Any site where the two interfering waves are moved upward will exhibit constructive interference. But it can also be seen when the displacement of both interfering waves is downward.
In this instance, a sine pulse with a maximum downward displacement of -1 unit interferes with a sine pulse with a maximum upward displacement of -1 unit.
Destructive interference:
Any position along the medium where the two conflicting waves have a displacement in the opposite direction will experience destructive interference. Destructive interference, for instance, happens when two sine pulses with maximum displacements of +1 unit and -1 unit come together.
The interfering pulses are traveling in opposite directions but have the same maximum displacement. When the two pulses are entirely overlapping, the end outcome is that they utterly destroy one another.
There is no resultant displacement of the medium's particles at the instant of total overlap. This "destruction" is not a state that lasts forever. In reality, it may be quite deceptive to claim that the two waves completely destroy one another.
When it is said that two pulses "destroy" or "cancel out" one another, what is really meant is that when they overlap, the effects of the two pulses on the displacement of a particular particle of the medium are negated or cancelled out by one another.