Recent content by moonjob

Wow. That is an awesome concept. I am so glad you introduced this to me! Thank you!

Thank you. That's kind of what I was thinking.

I will be starting PhD studies in the fall, but first I must decide which school I will attend. I am basing this on what field I want to go into. The choices are Condensed Matter/Quantum Information science or High-Energy Particle physics. I am having a little bit of difficulty deciding. I am...

It turns out that I forgot to bring along the l into the potential energy; that makes the units work out.

Hmm, you're right. I'll have to look through it again. The question (I may not have stated this) is looking for normal mode frequencies. According to my understanding, that means that all parts oscillate such that the phase difference between them doesn't change. You're correct that this does...

I wanted to add that solving algebraically (if you neglect the \dot\phi^2\phi term), one reaches the following equation: \ddot\phi - \frac{g(M+2m)}{l^2M}\phi = 0 Which appears to have too many factors of l in the denominator. I suppose the GRE could have been in error, but I want to know for...

Homework Statement This problem is from the 1992 GRE. A tube is free to slide on a frictionless wire. On each end of the tube is attached a pendulum. The mass of the tube is M. The length and mass of the pendula are l and m, respectively. Homework Equations It is given that one of the...

I can't go through algebra with the values already inserted... it's too messy... but here is my treatment on the relationship between the recoil energy and the excitation energy. I think I've shown that the former is definitely exceeded by the latter, using the quadratic equation approach you...

I know that this post is over a year old, but I saw this and felt I had to comment. The first excited state of the atom is 93.3 keV, as you said. When the atom decays into the ground state, however, this energy is not distributed completely to the gamma photon; some of the energy is imparted...

Thank you for the reply, but I actually meant that I won't be able to use a calculator. It's not allowed on the GRE!

I have been studying for the GRE and taking note of various approximations to use on the exam, but I am having a difficult time finding a way to evaluate the following without the aid of a calculator e^{-x}. The GRE practice book has a problem to which the answer is e^{-10} = 4.5 \times...