Solution to Problem #46 - Coupled Oscillators

[@AdityaSingh-dg5ex]

Professor you are the best person ever walked on earth.❤️

[@HariprashadRavikumar]

Ha ha ! My answer is correct ! Thanks professor ! Love you

[@PraneshPyaraShrestha]

How do you send answers?

[@HariprashadRavikumar]

@@PraneshPyaraShrestha only one way : through comment (KZbin)

[@esa062]

No single part of that is very difficult. It's just that I can't handle so many parts, not having thought of oscillations or done complicated math in 30 years.

[@EngMostafaEssam]

Sir,I can't understand why you neglect the force of weight😥

[@hanslepoeter5167]

So, I finished the computer simulation for this. It does not work that well for answering the question as i need a correct starting point for it. If i assume the spring length of both springs at rest at 1 meter, start the simulation with both springs at 1.2 meter ( as if i'm stretching both springs to 1.2 meter and then let go ) I get a period of about 35 seconds. That checks out. The problem is it's not stable. I get between 34 and 36. When i change spring 1 to 0.8 meter and then let go the result is completely unstable. So I only can confirm your outcome with this if i have a realistic starting point. I' ll try and make a search algorithm for that..

[@wendythebearboston5304]

Curiously when setting m1=m2 and k1=k2 omega(+) is omega*phi and omega(-) is omega/phi where phi is the golden ratio. This is also the case for problem 43 when the periods omega(s)=omega(p).

[@x0cx102]

These problems (coupled oscillators) have been showing up on recent usa physics olympiad (f=ma's) contests :)

[@aryanshshrivastava2650]

Sir, isn't this faster to do with matrix methods?

[@ulfhaller6818]

Aryansh Shrivastava, Yes, it is a little bit faster. I did it both way, just to check 👱🏻.

[@lglira]

Thanks Professor Lewin

[@AliRaza-sz9fp]

Sir I have a question.If earlier scientists thought that electric current is due to the flow of positive charges then I think that battery was discovered accidentally.I am right???

[@carpediemyes]

Why is omega the same for both springs ? Can't each spring oscillate at different frequencies ?

[@lecturesbywalterlewin.they9259]

>>>Can't each spring oscillate at different frequencies ?>>> *no not at resonance!* watch my 8.03 lectures where I discuss this in great detail.

[@sachinmishra4045]

Sir plzz guide me... Which book should I prefer to study about light...

[@lecturesbywalterlewin.they9259]

any college physics book is fine

[@sachinmishra4045]

@@lecturesbywalterlewin.they9259 Okk sir thanku.. one more question sir.. What will be the effect of magnetic field On the weight of the body? will the weight of the body will change inside the magnetic field?

[@lecturesbywalterlewin.they9259]

@@sachinmishra4045 The spring is made of metal. A moving metal in a B-field will produce Eddy currents and thus energy will be consumed. Thus the freq of oscill will go down.

[@sachinmishra4045]

@@lecturesbywalterlewin.they9259 Plzz explain me more I am not getting it sir how it is related to the weight of the body??

[@lecturesbywalterlewin.they9259]

@@sachinmishra4045 watch my 8.02 lectures about Eddy currents; you will then understand! good luck!

[@bryangohmppac6417]

Sir, do you have the special relativity lecture. And sir, actually the problem 43 is one of my 2013 olympiad exam question

[@lecturesbywalterlewin.they9259]

there are many SR lectures online. I did 3 Physics Problems which require SR. They are on this channel.

[@warfyaa6143]

u get 0.1804 , I get 0.1790 for Omega(-) , u get your video liked by me and we will still be friends .

[@lecturesbywalterlewin.they9259]

ofcoz I counted your result as correct!

[@ulfhaller6818]

warf warfe, Did you also get these numbers? ω² - = 0,032055053 ω² + = 0,467944947 ω - = 0,179039249 ω + = 0,684065017 f - = 0,028494982 f + = 0,108872329 Equation: ω² = (5±√19)/20

[@sushmitamaji1920]

Sir, do you have the lecture on Non - linear dynamics?? I can't understand it even going through the book. It becomes very difficult for me, Sir pls help me

[@lecturesbywalterlewin.they9259]

use OCW or Coursera or Udacity

[@sushmitamaji1920]

Lectures by Walter Lewin. They will make you ♥ Physics. Thank u Sir 😊