Recent content by tannerbk

No, use the Lagrangian, just make sure you are using only one set of generalized coordinates. I would use Cartesian.

Use the equation for the period of a pendulum to help you find Vb.

No. Many theoretical and expiremental physicists work on fusion. Also, suppose your initial argument were true, I can't think of many things I consider more benficial than knowledge.

Perhaps it would be easiest to write out the Lagrangian L = pq - H and use the formula for the generalized force F = \frac{\partial{L}}{\partial{q}} ; however, I haven't worked it out explicitly. I only suggest this because you're right, I'm not sure why \ddot{q} rather than \dot{p} gives...

A couple of hours - probably between 3-6 depending on how hard the chapter is and how thoroughly you do the homework / read the book. However, for harder classes like H104 you will probably have to go to office hours / discuss the problems with classmates and in my experience I've spent over 20...

I would never suggest taking 3 math classes in one semester, especially your first semester - as this will make completeling your breadth requirements extremely difficult. I would absolutely suggest taking math 54 and 55 first semester (if you are confident in your multivariable calculus, math...

Hi, I go to Berkeley and have taken math 104. It is quite difficult and I personally did not like the class. Then again, I don't like proof-based pure math classes, so it is a personal preference. In terms of the pre-requisites, what have you taken at Berkeley? If you haven't taken at least Math...

Thanks!

I tried before I posted this, can you provide a link?

I've read recently about systems with the ability to reach negative temperature: where entropy decreases as energy increases. I have a couple question regarding this. First, how is it possible to reach negative temperature without crossing absolute zero? Is there some discontinuity like a phase...

In general: < ψ_{i} | ψ_{j} > = δ_{ij}. Use the normalization condition ∫^{\infty}_{-\infty}dxdydz|ψ(x,y,z)|^{2}=1 to check the ground state is properly normalized. To calculate < r > use spherical coordinates.

I would suggest taking the derivative of your equation (1), giving \ddot{q}=\frac{\dot{p}}{m}e^{-\frac{q}{a}} - \frac{p}{ma}\dot{q}e^{-\frac{q}{a}} Now plugging in for \dot{p} gives: \ddot{q} = \frac{p^2}{2am^2}e^{-\frac{2q}{a}} - \frac{p}{ma}\dot{q}e^{-\frac{q}{a}} And from (1) we...

I believe they want you to use c_{1} and c_{2} to calculate <p> and use that to calculate Δp, since you have already calculated <p^{2}> . Hint: <H>=Ʃ|c_{n}|^{2}E_{n} would be an analogous formula to calculate the expecation value of the energy.

You are still confused about what wavefunctions you need to integrate over. Your integral should be the wavefunction given to you multiplied by the energy eigenstate, c_{n} = ∫√\frac{8}{3a}sin^{2}(\frac{{\pi}x}{a})√\frac{2}{a}sin(\frac{n{\pi}x}{a}) . For n=1 this will give you the probability...

No, the sum over all the individual probablities should equal 1. Show your work and we can help.