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Homework Help: Mangetic and electric field, optics and escape velocity questions

  1. Jun 27, 2010 #1
    http://img682.imageshack.us/i/77482562.jpg/" [Broken]


    I don't really understand these questions... Is there anyone who could tell me HOW to solve them? I don't ask about ONLY answers, I just want to understand how to solve these types of exercises.

    The things I know:
    1. the centrifugal force = the gravitational force
    Fg=GmM/r^2
    Fc=?

    2. the potential =0 (+1 and -1)

    5.
    [PLAIN]http://img717.imageshack.us/img717/8140/96746786.png [Broken]
    and
    [PLAIN]http://img806.imageshack.us/img806/4811/78862281.png [Broken]
    L>>|SM|, so r~12
    sin ~ 0.007
    so d*0.007= 1*633 d=......

    ok but how many interference maxima can be observed?? is there an equation for that?

    3. B inside = 0 because it's a sphere...
    4 - I have no idea how to do this o_O
     
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Jul 7, 2010 #2
    First, most of these are introductory physics; you might have better luck in that forum. (I'm new here myself.) Second, we're not supposed to give answers, just hints, so here:

    1.Good so far, except it's centripetal, not centrifugal. Write F=ma and think carefully about each variable.
    2.E is a vector. Add vectors by adding components.
    3.Gauss's law helps here.
    4.This one requires calculus. Look up the Biot-Savart law.
    5.sin x can't get bigger than 1.

    Good luck!
     
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