# Magnetic Moment, Electron Spin, Energy

#### roeb

1. Homework Statement

The PE of a magnetic moment in an external magnetic field is given by U = -u dot B. Calculate the difference in energy between the two possible orientations of an electron in a magnetic field B = .6k T

2. Homework Equations

3. The Attempt at a Solution

I realize electrons can have an up spin and down spin, but I am having a hard time doing this problem.

I believe I should be using g = 2 for the gyromagnetic ratio. So: (_h = h bar)
uz = -g uB JZ/_h
uB = e(_h)/(2me)

Unfortunately then I don't know what I should have for Jz. (This is defined by my book as "any type of angular momentum).

So I guess my problem is that I don't know what I should use for angular momentum, since n and l aren't defined in the problem. Can anyone help clear this up?

Related Introductory Physics Homework Help News on Phys.org

#### borgwal

Use the electron spin, S_z. Strange you would know about the gyromagnetic ratio but not about which angular momentum that refers to in the case of an electron!

### Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving