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: Magnetic field problem

  1. Feb 10, 2007 #1
    1. The problem statement, all variables and given/known data
    In an experiment you find that a small styrofoam ball of mass m can be suspended in mid-air by an electric field of magnitude c pointing straight downward, towards the earth.

    Its looking for the charge on the styrofoam ball, and I have no equation to help me solve for it.

    2. Relevant equations
    Lol thats what I'm lookin for.

    3. The attempt at a solution
  2. jcsd
  3. Feb 10, 2007 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    What is the equation for the force experienced by a charge q in an electric field E?
  4. Feb 10, 2007 #3
    k(q1)(q2) / l^2?
  5. Feb 10, 2007 #4


    User Avatar
    Gold Member

    You are given the magnitude of the E field. Note that much emphasis was placed on q and E. The force is proportional to product of two things...
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook