@X3QT0R
I had a 10:48 minute long mindgasm. Thank You @ MIT OCW
@69erthx1138
I had forgotten this simple derivation from solid mechanics, but when (mu/T) d^2y/d^2 = d^2y/dx^2 emerged from the analysis at 7:15 the lights came back on!
@bharathishrinivasan
yea its worthy. It helped me to understand schodinger eq. which actually derived from simple wave eq. in a string.
@stevenan93
best channel name
@billnolastname5078
I went to a public college. I only needed to watch this video 4 times before got it.
@richardsmith6488
Time 3:20, "What is dm? We know the length is Δx." I don't see how the length is Δx. Maybe (Δy^2 + Δx^2)^(1/2)? Any thoughts on how we can know Δx is the length?
@BYMYSYD
I like this simple videos that keep it under 10 minutes.
@alphalunamare
I am glad I watched and understood this :-)
@panazilian
i have apples here so i must have apples here, i love this guy
@vdabest2118
It’s so weird to finally start understanding these kinda physics lectures (I’ve understood 20% so far by the way)
@pablosevilla5259
Why do you get a C^2 out when you take the second derivative with respect to time?
@shawzhang4498
why the tension is the same on both sides?
@catgod5986
While I agree that Professor Lewin is an excellent teacher, I have a serious issue with his derivation of the wave equation. He assumes that the angle: theta is small, so that: -T*sin(theta) + T*sin(theta + delta-theta) reduces to T*delta-theta , and he later reduces: 1/cos^2(theta) to the value 1. This assumption isn't true in most cases and isn't true for the string he demonstrated in the first lecture. I searched the net and quickly found a better derivation that is only very slightly more complicated but does not need this assumption. You can see it at: http://math.seu.edu.cn/CourseFiles/20120505213457334.pdf. I think Professor Lewin should consider revising his derivation so that it at least applies to his in-class example. Of course, I'm just a student, so maybe I'm totally wrong and missed something here. Any comments pointing out what I missed would be appreciated. Thanks.
@nazmurrahmannobel11
You are great, sir.
@patipateeke
how come if you just have a rope, (and a constant tension) that will lead to the wave equation? There can be any motions inside this rope, not only waves.
@MonicaKn17
Wonderfully explained. And i love his enthusiasm too.
@Seracinfinity
Fantastic lecture.
@08muazahmed88
So why we use "Y double dot" if time is not define in the partial derivative of tension.
@Alex4LP
why dx --> Δx at 6:25 ?? I'm sorry but i think this demostration really doesn't work.
@TheAnalogyGuy