Recent content by turin

I don't know about this effective potential, so if you must understand your solution manual, then I cannot help you. I would do it this way: calculate the initial charges on each capacitor from your basic equation Q=CV (as you did) calculate the equilibrium charge after connection...

Your instructor wants you to try to understand your formula, which is based on a few ostensibly disparate concepts that have been combined for you into a neat little package. (Physicists get such a kick out of deriving equations like the one you used in your lab to calculate the mass from the...

Algebra. This is a quadratic equation. Put it into standard form and then find the roots for t (i.e. used the quadratic formula, but with t instead the of the traditional x).

No, it is not. It is based on Rydberg's direct empirical observation that wavenumbers come in series. It was basically a matter of (discrete) curve fitting (and almost two decades before Einstein's relation). @miniradman, Your instructor probably wants you to use the quantum-mechanical...

I did not read the scanned problem; I only read your typed version. For part (a) you forgot to multiply by the charge of the electron; what you have there is the potential (sans energy). There is also the ambiguity of the reference point. It looks like you chose the surface of the inner...

Sure, it would be MUCH easier using the BCH formula (almost trivial). I was assuming that the problem is an exercise to demonstrate a nontrivial exponentiation of operators, and if the point was to use the BCH formula, then they would have at least made the commutator more complicated (like...

There are operators A and B, and then there are parameters λ and μ; what indices?

You also have another equation for momentum from Quantum Mechanics. What is n?

I can't figure out why the imaginaryness of λ and μ is important (at least formally). Exponentiating an operator means nothing more than the infinite power series of the exponent (Taylor series). I think that it's actually technically defined this way. So, for example: exp(μA) = 1 + μA +...

projectile motion strikes again!

That depends on the convention, right? For instance, in Peskin, the convention is to use hbar as the base unit (of action). I don't recall seeing anyone use just plane h as the base unit, but it is just a convention.

Is there some form of ψ here that you are neglecting to tell us (like it is the wavefunction of the neutron)? If ψ is independent of E (or E0), then I don't see how it would make a difference (unless it's as silly as to realize to treat the neutron classically, so that t1-t0 depends inversely...

The radioactive source is at the center of a make-believe sphere, whose surface area is 4πD2. The detector window has an area of (π/4)b2. The ratio of the solid angle of your detector window Ω to the solid angle for the entire sphere 4π is approximately the ratio of the area of your...

I would assume that you just use E = h f = h c / lambda = hbar c k , no? (I'm assuming that the inverse lengths that the problem specifies are wavenumbers of photons that would be emitted from the corresponding energy differences.)

I agree with your point, Simon. Without clearly and consistently identifying the letters F, V, etc., we're all just guessing ...