Recent content by Yondaime5685

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    Converging Lasers of Different Wavelengths

    -UltrafastPED Thanks for that info. I'm starting to do Optics for my research and I'm slowly getting my feet wet. The "dogleg" setup will hugely help me. The idea is so simple, but effective. I don't know about cutting the lens in half, my adviser might kill me, but I'll give your other...
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    Converging Lasers of Different Wavelengths

    I hope this is the right place to ask this. It is an experiment question. I have a 785 nm laser and a 1550 nm laser and I need to converge them down to a point. Now I could just manually align the lasers on the same XY-plane and have them hit that spot, but for reasons I don't want to...
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    How to go about solving this first-order nonlinear differential equation?

    Thanks a lot! That made the problem a lot simpler. I can't believe I didn't carry that \eta over.
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    How to go about solving this first-order nonlinear differential equation?

    I saw this post at stackexchange: I ran across this post when trying to solve a homework problem. But I have no idea how he got that solution for that. When I use the Euler-Lagrange, I get this diff eq below. Here is the simplest form I have managed to get it in...
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    Tips on writing the Lagrangian

    Thanks. I'll just try to do as much problems with different scenarios as I can. And I'll keep your tip in mind.
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    Tips on writing the Lagrangian

    ^ Yeah sorry, that is what I meant. That hint helped me thanks. It is like watching a magic trick. Once you know the trick, it becomes simple. Haha. So do you have any tips in general on how to better this "intuition"...? Or is it just about gaining more confidence...?
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    Tips on writing the Lagrangian

    Hey guys. I'm trying to gather some tips that people have acquired that helps them write the Lagrangian for a system. Obviously, the classic examples are drilled into our heads over and over, but just when you think you can tackle any problem the professor throws at you, there is that tricky one...
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    Derivation of Potential Energy for two masses attached to three springs

    Ahh... That was my gap in my understanding. I don't know why I didn't see it that way from the beginning. With that in mind, I derived the right potential. Thank you guys for helping! :smile:
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    Derivation of Potential Energy for two masses attached to three springs

    Hmm... I see what you mean. Let me look into that in the morning. It is about 2:15 in the morning for me and I got to get some shut eye. From a quick glance, I would argue that I never wrote down my forces in "x_2-x_1" terms, so I would not run into that. But I'm sleep deprived so I may not...
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    Derivation of Potential Energy for two masses attached to three springs

    ^ Yes you are right. I just typed it wrong when I was reading it off of Taylor. Thanks For the integration, yes I made it really general and simplified, but it is right. I'm still integrating along the general x-axis since both variables, though they are named different, still vary in the...
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    Derivation of Potential Energy for two masses attached to three springs

    First of all, my question isn't completely unrelated to a homework question. I know how to answer that question using definitions in the book and mechanically get to the end. But I wanted to start from basic principles and arrive at the same answer. This lead to a contradiction which sent me on...
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    Quick help needed on a Matrix Multiplication

    -chogg Yes. That helps. I'm using Matlab and remember seeing a code in the User's Guide that probably does the same thing. Thanks. :tongue2:
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    Quick help needed on a Matrix Multiplication

    Okay, after experimenting with your post, micromass, I found out it does work for any value you want to pick off. So I want to thank you for that. But I have to translate this into coding and it seems like it is going to be more code to write this than just my original idea to use an if and else...
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    Quick help needed on a Matrix Multiplication

    -micromass Yes, that seems to work. But really what I need is what chogg stated. I need to able to "mask out", as chogg perfectly put it, more than one element. Will that work for picking out more than one element..? Thanks for the help. -chogg Yes, that is exactly what I need to do. You see...
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    Quick help needed on a Matrix Multiplication

    I have a small problem where I remember I learned it in the past. But now I can't seem to recall how to do it. I searched on google, but I think even though it is probably really easy, I may not have worded it right to get the references I want. So I decided to ask here. Here is the problem...
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