Lagrangian pendulum

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PhysicsHelps

11 жыл бұрын

An example of using the Lagrangian to find the equation of motion for a system.

Пікірлер: 29

@RexGalilae 8 жыл бұрын

I'm still in 12th grade and I think your excellent way of teaching is directed at someone who's in his first year of calculus. It's hard to get confused on any part of your video due to the high amount of emphasis on detail. Keep up the great work!^_^

@vegeta94x 9 жыл бұрын

Brilliant video! Thanks a lot for taking the time and effort to make such great videos. You make complex material easy to understand. Using different colours makes everything even more clear.

@Animegamernerd1 9 жыл бұрын

Edward Xavier I agree with you bro the colors were colorful bro. This guy so much better than my prof. He cant teach and he marks like a mad man. I made a decimal error he gave me one mark. :(

@sg4863 9 жыл бұрын

You forgot a minus in the last line...

@karimkhan1312 8 жыл бұрын

i am addicted to u r lectures - i see again and again

@benjamincordes207 9 жыл бұрын

Thanks for sharing this. Great explanations and very clear.

@Chr0nalis 10 жыл бұрын

Nice explanation , thanks

@nilaksh007 5 жыл бұрын

Really good.

@PhysicsHelps 11 жыл бұрын

Ah, thank you. I'll add a note. Good catch!

@wadiesama 7 жыл бұрын

Thank You Very Much, you Are Better Than my Teacher

@inox1ck 6 жыл бұрын

2:00 The length of a full circle is 2πl so l•θ is a length of a segment of θ radians.

@RSP13 11 жыл бұрын

Thank YOU

@sanjayregmi4908 8 жыл бұрын

@PhysicsHelps r u taking QFT by any chance?

@khanTatifur 8 жыл бұрын

The positive sign in the last line is absolutely correct if you consider downward positive. For that you must consider the potential energy to be negative.

@ernestschoenmakers8181 4 жыл бұрын

Not true must be negative because gravity is a restoring force in this case.

@AwesomeAngryBiker 5 жыл бұрын

At 7:00 should the Euler Lagrange eqn be the opposite way around?

@kennyimammahardika3868 5 жыл бұрын

It's the same. If a-b=0, then b-a=0

@karimkhan1312 8 жыл бұрын

i wish i can meet u sir

@ultimatequantumguy3131 6 жыл бұрын

Quick question: Is there any way of finding an equation describing the motion with respect to time from that equation which is left at the end? (As in one of the form theta = f(t))

@PhysicsHelps 6 жыл бұрын

Yes. It's a differential equation. The quintessential physicist's method for solving differential equations is to guess that it's an exponential and then work out what some constants should be. This one ends up being sinusoidal (i.e., the real part of an exponential with an imaginary number in the exponent).

@ultimatequantumguy3131 6 жыл бұрын

Thanks! Are there similar solutions for most ODEs, or is this a special case for having a solution?

@PhysicsHelps 6 жыл бұрын

Exponential solutions (including oscillatory ones) are pretty common in physics scenarios. To be honest with you, my approach to differential equations is to guess an exponential solution, and if that doesn't work, I go to wolfram alpha.

@ultimatequantumguy3131 6 жыл бұрын

Thanks so much for all your help, it's really appreciated! I have seriously fallen in love with this Lagrangian!