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Homework Help: Elevator and scale

  1. Oct 5, 2005 #1
    A person stands on a bathroom scale in a motionless elevator. When the elevator begins to move, the scale briefly reads only 0.67 of the person's regular weight. Calculate the acceleration of the elevator.

    how do i start this problem? help please!!
     
  2. jcsd
  3. Oct 5, 2005 #2

    hotvette

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    do you have any equations of motion you are suppose to use?
     
  4. Oct 5, 2005 #3
    <tex>w=mg<txt>
    when he's not accelerating his weight is something and g=32.2 ft/sec2. When the elevator accelerates his weight drops to .67 of what it was. (his mass hasn't changed)
     
  5. Oct 5, 2005 #4
    <tex> w=mg<tex> I really wish I could make LATEX work.
     
  6. Oct 5, 2005 #5

    hotvette

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    Use [ and ] instead of < and >
     
  7. Oct 6, 2005 #6

    andrevdh

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    The person is experiencing two forces, his weight and the force from the scale (the reading on the scale is caused by the action/reaction force of this). The vector sum of this two forces gives the resultant "elevator acccelerating force" on the person according to N2.
     
  8. Oct 6, 2005 #7

    HallsofIvy

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    And don't forget the / before the ending "tex":

    [ tex ] e^{-x^2} [ /tex ]

    gives [tex]e^{-x^2}[/tex].

    The "Math Message Board" uses < > instead of [ ] and I am forever getting them mixed up!
     
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