1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: What is the magnitude of the magnetic field?

  1. Aug 1, 2011 #1
    1. The problem statement, all variables and given/known data

    The nucleus of a Tl atom (Atomic mass = 203, element #81) has a magnetic moment of 1.611 µn. A magnetic field is applied to it and its NMR frequency determined to be 3.90 MHz. What is the magnitude of the magnetic field?

    2. Relevant equations

    torque = magnetic moment x magnetic field
    radius = mv/qB
    v = rw
    Fcentripetal = mv^2/r

    3. The attempt at a solution
    I tried (magnetic moment x magnetic field)/radius = mv^2/r but this always leaves me with r in the equation, which is unknown.
  2. jcsd
  3. Aug 2, 2011 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    You can try looking in your textbook, or do an online search, for "Larmor precession" or "precession of magnetic moment" or something along those lines.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook