- #1
Ming0407
- 8
- 0
my Q1 ans. when U=100v, wavelength=1.228 x 10^-10 m
when U=10000v, wavelength=1.228 x 10^-11 m
Q2 ans. help me...
Last edited:
Q2 Help: Quantum Mechanics U=100v & U=10000v Wavelengths
- Thread starter Ming0407
- Start date
Click For Summary
Homework Help Overview
The discussion revolves around a quantum mechanics problem involving the calculation of wavelengths at different potentials (U=100v and U=10000v) and the application of wave equations. The original poster seeks assistance with the second question after providing their answers for the first.
Discussion Character
- Exploratory, Assumption checking, Problem interpretation
Approaches and Questions Raised
- Participants discuss the need for the original poster to demonstrate their attempts at a solution, referencing the forum's policy. There are inquiries about the original poster's background in mathematics, particularly calculus, which is essential for understanding the differentiation required in the wave equation.
Discussion Status
The conversation highlights a lack of consensus on how to proceed, as the original poster expresses difficulty with differentiation and admits to not having studied the necessary mathematical concepts. Some participants suggest that without a foundational understanding of calculus, it may be challenging to provide meaningful help.
Contextual Notes
There is an indication that the original poster may be attempting quantum mechanics without sufficient mathematical preparation, raising questions about their readiness for the material.
my Q1 ans. when U=100v, wavelength=1.228 x 10^-10 m
when U=10000v, wavelength=1.228 x 10^-11 m
Q2 ans. help me...
- #2
Kurdt
Staff Emeritus
Science Advisor
Gold Member
- 4,859
- 6
Welcome to PF! I'm afraid you will need to show your attempt at a solution before anybody can help you. It is the policy of this forum.
- #3
Ming0407
- 8
- 0
Sorry, i don't know the policy of this forum. Anybody can help me?
- #4
Kurdt
Staff Emeritus
Science Advisor
Gold Member
- 4,859
- 6
Question 1 seems to be fine. You've found the momentum and used the de Broglie wavelength equation. For question 2 you will have to use the plane wave [itex]\Psi (x,t) = Ae^{i(kx-\omega t)}[/itex] in the wave equation and perform the differentiations. Then you should be able to do part one and part two.
- #5
Ming0407
- 8
- 0
i don't know how to perform the differentiation. because i have not study differentiation, i don't know question 2 too.
- #6
malawi_glenn
Science Advisor
- 6,735
- 2,436
Ming0407 said:
Well why are you doing QM if you haven't done enough math before?
And there are tons of tutorials on the internet on calculus. Do you want us to show you some of those?
- #7
TimNguyen
- 79
- 0
Ming0407 said:
You're taking QM and have not taken Calculus I?
How is that possible?
- #8
Kurdt
Staff Emeritus
Science Advisor
Gold Member
- 4,859
- 6
Ming0407 said:
I'm not sure we can help you other than giving you the answer in that case, which is against the spirit of the forum. I could spend 30 minutes typing out a tutorial on how to differentiate exponentials but frankly I don't think it would help when you have never taken any calculus and you're doing a QM course.
I must ask, are you self-studying or on a college or university course?
Similar threads
- · Replies 27 ·
- · Replies 6 ·
- · Replies 2 ·
- · Replies 1 ·
- · Replies 7 ·
- · Replies 5 ·
- · Replies 7 ·
- · Replies 7 ·
- · Replies 11 ·