Quantum Mechanics / Uncertainty Principle Question

fazer2014
Messages
8
Reaction score
0

Homework Statement



The square of a wave function gives the probability of finding a particle at a given point. What is the probability of finding an electron in a 1s orbital within a volume of 1pm^3, centred at:
a) the nucleus
b) 50pm away from the nucleus?

Homework Equations



Heisenberg Uncertainty Principle

The Attempt at a Solution



I sense that this is actually a straightforward question, but I just can't get my head around what it's asking. I feel like the first sentence is not actually relevant to solving the question, just a little ditty of information? I'm also thrown by the 'centred at' thing. If anyone can offer an explanation for how to think about this problem it would be greatly appreciated, thanks.
(Sorry, this is actually for a chemistry class, but I searched the forums and there are a few questions on this topic, though none I could find that answered this specific question).
 
Physics news on Phys.org
fazer2014 said:

Homework Statement



The square of a wave function gives the probability of finding a particle at a given point. What is the probability of finding an electron in a 1s orbital within a volume of 1pm^3, centred at:
a) the nucleus
b) 50pm away from the nucleus?

Homework Equations



Heisenberg Uncertainty Principle

The Attempt at a Solution



I sense that this is actually a straightforward question, but I just can't get my head around what it's asking. I feel like the first sentence is not actually relevant to solving the question, just a little ditty of information? I'm also thrown by the 'centred at' thing. If anyone can offer an explanation for how to think about this problem it would be greatly appreciated, thanks.
(Sorry, this is actually for a chemistry class, but I searched the forums and there are a few questions on this topic, though none I could find that answered this specific question).

It is not really an uncertainty question.

First, note that the probability is not given by the square of the wave function! The probability of finding the particle in a small volume dV is actually given by

\bigl| \psi (r, \theta, \phi) \bigr|^2 \, dV

So just square the wave function at the values of r given in the questions and multiply by the small volume.
 
I see... thanks, I understand in theory. But we weren't actually given a wave function. So is it just a thought experiment or something?
 
You were given the state (1s orbital). I suggest looking up the wave function for the ground state in a hydrogen-like potential.
 
Hello everyone, I’m considering a point charge q that oscillates harmonically about the origin along the z-axis, e.g. $$z_{q}(t)= A\sin(wt)$$ In a strongly simplified / quasi-instantaneous approximation I ignore retardation and take the electric field at the position ##r=(x,y,z)## simply to be the “Coulomb field at the charge’s instantaneous position”: $$E(r,t)=\frac{q}{4\pi\varepsilon_{0}}\frac{r-r_{q}(t)}{||r-r_{q}(t)||^{3}}$$ with $$r_{q}(t)=(0,0,z_{q}(t))$$ (I’m aware this isn’t...
Hi, I had an exam and I completely messed up a problem. Especially one part which was necessary for the rest of the problem. Basically, I have a wormhole metric: $$(ds)^2 = -(dt)^2 + (dr)^2 + (r^2 + b^2)( (d\theta)^2 + sin^2 \theta (d\phi)^2 )$$ Where ##b=1## with an orbit only in the equatorial plane. We also know from the question that the orbit must satisfy this relationship: $$\varepsilon = \frac{1}{2} (\frac{dr}{d\tau})^2 + V_{eff}(r)$$ Ultimately, I was tasked to find the initial...
Back
Top