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Homework Help: Force and Displacement

  1. Jul 25, 2007 #1
    1. The problem statement, all variables and given/known data
    Find the work W done on the block by the force of magnitude F = 85.0N as the block moves from xi = -3.00cm to xf = 5.00cm.

    2. Relevant equations
    W = F*S*cos(theta)

    3. The attempt at a solution
    W = (85.0N)(-3cm-5cm)*1
    W = -260J

    Am I missing something?
  2. jcsd
  3. Jul 25, 2007 #2
    The definition of displacement.
  4. Jul 25, 2007 #3


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    And a consistent set of units
  5. Jul 25, 2007 #4
    Let me try this again....

    W = (85.0N)(3cm+5cm)*1
    W = 680J

    (3cm + 5cm) because the block is moving from -3cm to 0 and from 0 to 5cm. This gives us a grand total of 8cm the block was moved. Sorry for the rather rudimentary question.
  6. Jul 25, 2007 #5
    a calculator??
    and check the units
    newton * meter = joule
  7. Jul 25, 2007 #6
    God, that was terrible. I'm going to stop right now and start again tomorrow. Sorry for the waste of time.
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