Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Electric Charges, Electric Forces and Electric Fields

  1. Apr 11, 2010 #1
    1. The problem statement, all variables and given/known data

    An object with a net charge of 24 x 10^-6 Coulombs is placed in a uniform electric field of 610 N/C, directed vertically. What is the mass of this object if it floats in this electric field?

    2. Relevant equations

    Felectric = kC (q*q/r^2)
    Electric Field= kC (q/r^2)
    E= Felectric/q

    3. The attempt at a solution

    I know I need to use F=ma, but I do not know the acceleration. I don't know how to solve this
  2. jcsd
  3. Apr 11, 2010 #2
    Which formula can be used to find the strength of the electric force due to the field?
  4. Apr 11, 2010 #3
    Electric field = Electric force/ q (charge of object)
  5. Apr 11, 2010 #4
    (Electric field equals the electric force divided by the charge of the object)
  6. Apr 11, 2010 #5
    Once the electric force is calculated, it must be equal to the gravitational force since the charge is floating. What formula is used to calculate the gravitational force acting on a mass?
  7. Apr 11, 2010 #6
    F= mg
  8. Apr 11, 2010 #7
    Force of gravity = mass x 9.8
  9. Apr 11, 2010 #8
  10. Apr 11, 2010 #9
    Wow thanks! haha I may have some more questions soon too :)
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook