Constructive vs. Destructive Interference

$\lambda=\frac{h}{p}$

Sydney Pell 2E
Posts: 100
Joined: Wed Sep 11, 2019 12:17 am

Constructive vs. Destructive Interference

In my notes, it says that diffraction patterns may result from constructive or destructive interference. What is the difference between these two and do they result in different diffraction patterns?

Posts: 45
Joined: Fri Aug 30, 2019 12:18 am

Re: Constructive vs. Destructive Interference

Constructive is when the peaks of two of the waves do not clash, combine, and then result in a larger wavelength.
Destructive is when the peaks of two wavelengths do not line up, combine, and result in a smaller wavelength. If the trophs are the same size, they will cancel out completely. I recommend checking out the module for a more in-depth explanation over these. Also, looking at pictures of this will help you understand the concept more.

katrinawong3d
Posts: 40
Joined: Sat Aug 17, 2019 12:17 am

Re: Constructive vs. Destructive Interference

Constructive interference is where two waves are added together, while in destructive interference, the two waves cancel each other out.

Maya Serota 3G
Posts: 53
Joined: Tue Sep 24, 2019 12:17 am

Re: Constructive vs. Destructive Interference

With constructive interference, is the resulting amplitude just the lengths of the individual waves added together? Or can it not be measured that way?

Jasmine Kim 1L
Posts: 71
Joined: Fri Aug 02, 2019 12:16 am

Re: Constructive vs. Destructive Interference

In constructive interference, the peaks and troughs (highest and lowest parts) of a wave align and the amplitude of the combined wave increases (it gets taller).
In destructive interference, the peaks of one wave align with the troughs of the other and vice versa and the resulting wave's amplitude is smaller.
I don't know what happens if the peaks and troughs don't match up perfectly or if the wavelengths are different, but I think we don't have to know this stuff. Just these 2 diffraction patterns.

Jasmine Kim 1L
Posts: 71
Joined: Fri Aug 02, 2019 12:16 am

Re: Constructive vs. Destructive Interference

Maya Serota 3G wrote:With constructive interference, is the resulting amplitude just the lengths of the individual waves added together? Or can it not be measured that way?

I think it does work like that. The book doesn't say anything, so I don't think we need to know it for chem, but I remember learning that in AP Physics.