An attempt frequency for a harmonic oscillator?

Duave
Messages
81
Reaction score
0
An "attempt frequency" for a harmonic oscillator?

Homework Statement



What is the "attempt frequency" for a harmonic oscillator with bound potential as the particle goes from x = -c to x = +c? What is the rate of its movement from -c to +c?

Homework Equations



v =\frac{1}{2π}\sqrt{\frac{k}{m}}

ω=\sqrt{\frac{k}{m}}


The Attempt at a Solution



1. x(t) = Acos(ωt)

2. \frac{d x(t)}{dt} = -Aωsin(ωt)

3. v(t) = \frac{d x(t)}{dt}

4. v(t) = -Aωsin(ωt)

5. -\frac{v(t)}{Asin(ωt)} = ω

6. ω = -\frac{v(t)}{Asin(ωt)}


4. Conclusion


Is the expression (equation) below the proper equation to use to determine the "attempt frequency" for a harmonic oscillator with bound potential as the particle makes its way between x = -c and x = +c?

ω = -\frac{v(t)}{Asin(ωt)}?
 
Physics news on Phys.org
Define "attempt frequency"?
Define "rate of movement"?
State these definitions in words and compare with what you've done.
 
  • Like
Likes 1 person
Thank you very much Simon.

The only problem is I've looked all around the universe and could barely even find a source that said even literally said "attempt frequency". I don't know what the definition is.

And, "rate of movement" to me is defined by some measurement over time, but, I still can't put 2 and 2 together, just because it's definition is so straight forward.

I wrote all the things in my question, because I needed someone to correct it for me. I'm have not found anything that could confirm its "correctness".

Thanks
 
If you don't know what those two terms mean, then you cannot do the problem.

Googling "attempt frequency" gets lots of examples of it's use.

Googling the "definition attempt frequency" suggests:
"attempt frequency" is the rate that a bound particle "attempts" to escape the potential.
http://encyclopedia2.thefreedictionary.com/attempt+frequency
... so how many opportunities per second does the particle have to escape?

"rate of movement" could refer to dx/dt - the velocity ... but why not just say "velocity"?
It could also refer to the rate that particles escape the well.

Both of these are used quite a lot.

What does the value of c signify? Is it the classical limits for a particle with a particular energy or some arbitrary point inside those limits?

If this is part of coursework then you should have had these terms used as part of the course somewhere.
The context will help - like: is this part of the course on SHM in general or about nuclear physics or what?
Since you have not found any such reference - you should go ask the person who set the problem.
 
  • Like
Likes 1 person
Simon,

-c and +c are the bounds. Okay look at this:


1. x(t) = Acos(ωt)

2. \frac{d x(t)}{dt} = -Asin(ωt)

3. \frac{d x(t)}{dt} = v(t)

4. \frac{d x(t)}{dt} = velocity

5. v(t) = -Asin(ωt)


How does step five look? I even took the derivative of the position, which would be the velocity.

Thanks again
 
You have decided to interpret "rate of movement" to mean "velocity"?
Step 2 is incorrect. Hint: chain rule.

You could have checked this yourself by checking that the units on the RHS of equ5 match the units on the LHS.
 
Thread 'Need help understanding this figure on energy levels'
This figure is from "Introduction to Quantum Mechanics" by Griffiths (3rd edition). It is available to download. It is from page 142. I am hoping the usual people on this site will give me a hand understanding what is going on in the figure. After the equation (4.50) it says "It is customary to introduce the principal quantum number, ##n##, which simply orders the allowed energies, starting with 1 for the ground state. (see the figure)" I still don't understand the figure :( Here is...
Thread 'Understanding how to "tack on" the time wiggle factor'
The last problem I posted on QM made it into advanced homework help, that is why I am putting it here. I am sorry for any hassle imposed on the moderators by myself. Part (a) is quite easy. We get $$\sigma_1 = 2\lambda, \mathbf{v}_1 = \begin{pmatrix} 0 \\ 0 \\ 1 \end{pmatrix} \sigma_2 = \lambda, \mathbf{v}_2 = \begin{pmatrix} 1/\sqrt{2} \\ 1/\sqrt{2} \\ 0 \end{pmatrix} \sigma_3 = -\lambda, \mathbf{v}_3 = \begin{pmatrix} 1/\sqrt{2} \\ -1/\sqrt{2} \\ 0 \end{pmatrix} $$ There are two ways...
Back
Top