Recent content by jaobyccdee

In measuring the x component of angular momentum of a state, by using the expectation value calculation of Lx, i got i/3 h bar - i/3 h bar, does this means that the probability of h bar is i/3 and the probability of 0 h bar is 0 and the probability of -h bar is i/3? If so, when is the...

The letters next to p and L should be subscripts. [Lz, px] = [xpy − ypx, px] = [xpy, px] − [ypx, px] = py[x, px] −0 = i(hbar)
py 1.In this calculation, why is [x, px] not 0 even they commute? 2.Why is py put on the left instead of the right in the second last step? i thought it should be...

[b]1. The problem statement, all variables and given/known A general one dimensional scattering problem could be characterized by an (arbitrary) potential V (x) which is localized by the requirement that V (x) = 0 for |x|> a. Assume that the wave-function is ψ (x) =  Ae^(ikx) + Be^(-ikx)...

thank you!:)

Homework Statement I am reading about electrodynamics, and in different formula, there is a SI form and a Gaussian form. Homework Equations What is the relationship in the different unit system for c or B or E and other relative variables? The Attempt at a Solution sometimes...

D is not linearly independent, and L has to be all one times a scalar. How should i ask MATLAB to build such a matrix?

Homework Statement I am trying to run a model in matlab. D is a 2 by 3 matrix, Knowing that DL=0, which means L is mapped to the null space. Homework Equations How can i find L so that it is a 3 by 3 matrix with all its entries being one times a scalar. The Attempt at a Solution...

What's the difference between short term memory and working memory? Is there any physiological difference?like difference in neural network formation? Thx!

I have a 8000x600 Matrix called V. How can i add the colume 1,5,9,13,17... (all colume of (4*i+1) for i from 0 to 149) of the vector?

1. If there are the same number of positive charge and negative charge, then there's no net charge, and thus no electric field? 2. Can i say since a constant current has a magnetic field that doesn't change, so an electric field is not induced? 3. If the number of positive charge and negative...

Yes, so negative charges go one way, and positive charges go another direction. Isn't it?

Aside from magnetic field, Does a wire carrying current induce also an electric field? If yes, what rule should i use to find its direction?

Thx a lot! So, if we have {up, up, down}, does it mean we have only walked one step and should see it as a vector (up, up, down} in 3D space? So, R (the position) does depend on the dimensionality? But then how does the position relate to the number of steps? I think i am confused by the number...

thx for replying. But i still have a question. What's the difference then between having three steps in 1D and 1 step in 3D?

Why are there 8 possible moves in 3D random walk? With R being the distance from the origin, how is its relationship with the number of steps and dimensionality? Thx!