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Homework Help: Homework HELP!

  1. Jan 4, 2005 #1
    The force of gravity is twice as great on a 2-kg rock on a 1-kg rock. Why does the 2-kg rock not fall with twice the acceleration?
     
  2. jcsd
  3. Jan 4, 2005 #2

    dextercioby

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    [tex] F=ma [/tex]
    If the force is the product between the mass and the acceleration,figure out yourself...

    Daniel.
     
  4. Jan 4, 2005 #3
    They both have the same mass and acceleration! Right?
     
    Last edited: Jan 4, 2005
  5. Jan 4, 2005 #4

    dextercioby

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    Okay,for the first body write
    [tex] G_{1}=m_{1}a_{1} [/tex](1)
    And for the second
    [tex]G_{2}=m_{2}a_{2} [/tex](2)

    Divide (1) through (2)
    [tex] \frac{G_{1}}{G_{2}}=\frac{G_{1}a_{1}}{G_{2}a_{2}} [/tex](3)
    Use the fact that [itex]G_{1}[/itex] is two times [itex]G_{2} [/itex] and that [itex]m_{1}[/itex] is 2Kg,which is two times the value of [itex]m_{2}[/itex] which is 1Kg.Then
    [tex] 2=\frac{2a_{1}}{a_{2}} \Rightarrow a_{1}=a_{2}[/tex]

    Daniel.
     
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