Lecture 4 | Modern Physics: Classical Mechanics (Stanford)

Lecture 4 of Leonard Susskind's Modern Physics course concentrating on Classical Mechanics. Recorded November 5, 2007 at Stanford University.

This Stanford Continuing Studies course is the first of a six-quarter sequence of classes exploring the essential theoretical foundations of modern physics. The topics covered in this course focus on classical mechanics. Leonard Susskind is the Felix Bloch Professor of Physics at Stanford University.

Complete playlist for the course:
http://youtube.com/view_play_list?p=189C0DCE90CB6D81

Stanford Continuing Studies: http://continuingstudies.stanford.edu/

About Leonard Susskind: http://www.stanford.edu/dept/physics/people/faculty/susskind_leonard.html

Stanford University channel on YouTube:
http://www.youtube.com/stanford

Category:

Education

Tags:

• Science
• physics
• math
• theory
• relativity
• equation
• formula
• newton

[opendevs]

Thank you for putting up these great lectures Stanford.

[rahulilrplac]

I am a software engineer by profession but just fell in Love with physics after 'understanding' it through these lectures.

Am actually planning to quit my job and do a Phd...incidentally in Physics.

Thank you Stanford. Thank you Suskind.

You are doing a great service to the humanity. Trust me on this one :)

[grunder20]

Give me more time to absorb his discussion! great work!

[SalsaTiger83]

@csmcmillion ok, then I am even stupider ;-)

[csmcmillion]

@SalsaTiger83 I wasn't talking so much about Classical Mechanics - this isn't bad. I've been through some of the others, such as Quantum Entanglements, QM, SR/Relativistic Field Theory and GR that are way tougher. Those are the ones that I'm barely hanging onto.

[SalsaTiger83]

@csmcmillion I have the same problem. But I think that is just the feeling of overwhelm, which indicates my brain working to overcompensate for the demands put on it. The problem is that in such lectures it is not always possible to make sense of where the stuff is going. Here you need to know that the goal is to find either the complete functions for the coordinates of the particles/etc or enough information to solve it numerically. Also try to write down the equations yourself.

[csmcmillion]

@SalsaTiger83 These lecture series pretty much show me I'm not physics PhD material. I mean, these aren't even full-blown grad classes and I'm barely able to hang on.

[SalsaTiger83]

I think I get the "how" but I can't figure out the motivation behind all this yet... What is this displacement bussiness useful for?

[SalsaTiger83]

@csmcmillion computer engineer + physics phd = on the best way to become a highly paid quant specialist on wall street

[csmcmillion]

"I am a software engineer by profession... Am actually planning to quit my job and do a Phd...incidentally in Physics"

= UNEMPLOYED

[PLecN]

@savvvvvvvvvvy

In one variable ... suppose we know value of f(a), then we can approximate f(a + dx) where dx is small by f(a + dx) approx f(a) + f'(a)dx

Now, if f'(a) = 0 then this simplifies to f(a + dx) approx f(a)

So if f'(a) = 0 then changing 'a' by a small amount doesn't change f hardly at all. Exactly the same can be said about fn's of many vars but now have to consider small changes in more than direction. Works out very similar.

[savvvvvvvvvvy]

I was just wondering whether somebody could help me out regarding what's said in the lecture. When Susskind talks about the function of many variables [at about 23 mins], f (alpha i), he says at the minimum, delta f = 0. I don't really understand what he means when he says that if a small change in delta alpha i occurs, the function doesn't change to first order. I'd be really grateful for any help :)