Deriving Young’s Double Slit Interference Formulas

In this video, I derive two different, but related, versions of Young’s double slit interference equations. These equations are used to find the points of constructive interference on a screen a distance D away.

[krumkutsarov]

the only video that explained why the angle is concidered 90 degrees. I didn't understand it watching so many other explainations. Good job!

[theeggsquidzidboi]

This video is so thoroughly explained, but in a way that is easy to comprehend. Not to mention the approximations which few sources seem to acknlowedge.

Thanks so much.

[StudywithmeinPakistan]

Excellent video. I also teach physics, in Pakistan. I was unable to find a way how to explain theta = theta to my students, so here it is a great video.

[okayokay]

Holy shit….dude this video is so underrated and best one I’ve ever saw……thank you so much for this

[ihorprotsenko]

Finally someone covered the angle theta which is introduced in the books out of nowhere. It is useful to that we take central maximum as our reference point.

[rud___boy]

The only satisfying answer to the demonstration of both Young's Experiment formulas I could find. Understanding that for n=1 the second beam could only travel one more wavelength was such an "AHA!" moment. Same with how the light beams could be considered not only parallel, but coincident as well. Elegant and to the point.

[sonics]

Thanks for this video. I appreciate your acknowledgement of the assumptions used here, specifically that the 3 lines are assumed to be parallel. My textbook completely glossed over this fact and skipped to the diagram which had me questioning myself since the geometry didn't line up :)

[baralike]

Thank you so much for clarifying that the lines being parallell is an approximation. I kept finding that they had to be parallell when trying to derive this, which confused the hell out of me. Neither my teacher nor my book mentioned it.

[koungmeng]

Thank you for the simple and informative explanation.

[sonderman]

Thanks for explaining the assumptions which made it all clear.

[koroespinacas]

fantastic video. Really concise clear and t the point. thank you

[grooveharsh]

really good for concept building...appreciate the work

[chrisorr]

Good video! I just want to point out that if you are strictly using a double slit, the maximum amplitude of each maxima should decrease as you move away from the center. If you use an entire grating, what is shown would be basically accurate

[dyqweghrh]

thanks for the videoand for clarifying that the lines being parallell is an approximation, this point made me so confused until i didnt watch the video

[purplebeast]

My teacher has been explaining this to us in multiple lessons but i never got it but i immediately understood it by watching ur vid once

[khooshuaiqi]

Thank you so much bro, I only understood from you for this topic

[martinsanchez-hwfi]

Does the difference of path lengths really always increase? When going in one direction I really would think both of the path lengths would grow after one of them had become completely perpendicular to the wall where the slits are

[aadilhasan]

thank you this works really well for a level

[dinodubroja]

Pattern does not oscilate from zero to some maaximum, its not a sinusoidal. Every peak getss lower and lower when you get further from center

[methaqallami]

Great explanation , thank you so much