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Homework Help: Two Masses One on Table, One Hanging

  1. Sep 29, 2012 #1
    1. The problem statement, all variables and given/known data

    A block of mass1 5.0 kg is on a table that bonds a coefficient of friction of 3.00. Mass1 is attached to Mass2 by a string, and Mass2 is hanging over the table. The system is released from rest for it to accelerate.

    2. Relevant equations

    F fric = ╬╝Fnormal

    3. The attempt at a solution

    [itex]\sum Fx of Mass1[/itex] = F tension - F friction

    [itex]\sum Fy of Mass1[/itex] = 0

    [itex]\sum Fx of Mass2[/itex] = 0

    [itex]\sum Fy of Mass2[/itex] = FW - F tension

    Is tension created by the mass1 or mass2?
    im guessing both? but that doesn't make any sense...
  2. jcsd
  3. Sep 29, 2012 #2
    1. Where is m3?
    2. Is coefficient of friction of 3.00 is between the block and table?
  4. Sep 29, 2012 #3
    no m3.....

    2. yes
  5. Sep 29, 2012 #4
    ok wrong interpretation.

    Find net force on each block.
    Both will accelerate at equal rate for the string is massless and inextensible.
    Last edited: Sep 29, 2012
  6. Sep 29, 2012 #5
    oops one on table, one hanging
  7. Sep 29, 2012 #6
    Use Newton's 3rd law.
    The hanging block will pull the block on the table.
    The block on the table will pull the hanging block with equal force.
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