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Homework Help: Force Problem

  1. Oct 28, 2008 #1


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    1. A beam consisting of around 1.0 1015 electrons per second, each of mass 9.1 10-31 kg, paints pictures on the face of a TV tube. Assuming that the electrons are absorbed by the screen and exert an average net force on it of 0.9 10-7 N, what is their average speed at impact?

    2. Favg = p/t and p=mv

    3. These are the two formulas given, but I'm not sure how to solve for speed
  2. jcsd
  3. Oct 29, 2008 #2
    Try starting the problem, and writing down your thought process.

    Write and sketch about what you already know from what the problem tells you - then see if you can use that to work out what you don't yet know.
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