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Homework Help: Fun with Combining Eqations

  1. Feb 14, 2005 #1
    what is the process for combining 2 equations?
     
  2. jcsd
  3. Feb 14, 2005 #2

    dextercioby

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    What do you mean...??

    Daniel.
     
  4. Feb 14, 2005 #3
    for example i have to combine These two equations for uniform circular motion and sole for T (the period of the motion)

    Eq. 1 V = 2 pi(r) / T

    Eq. 2 V^2 = (r / m)F
     
  5. Feb 14, 2005 #4

    dextercioby

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    The first one looks familiar,you may wanna explain what does the second represent...?

    Daniel.
     
  6. Feb 14, 2005 #5
    the original equation is F = m(v^2 / r) but instead that one is solving for velocity squared when r and m are fixed but the question is asking me to combine the two equations and solve for the variable T (time for 1 revolution)

    does any1 know how to combine them??
     
    Last edited: Feb 14, 2005
  7. Feb 14, 2005 #6

    DaveC426913

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    Didn't you pick this up in High School?

    Since the left side of an equation equals the right side...

    - You have Eq 1 that sez v=...

    - And Eq 2 that has a V in it. So substitute one for the other. Now you have one big equation. Then just rearrange it until you have T alone on the left.
     
  8. Feb 14, 2005 #7

    guess i must have been asleep for that lesson
     
  9. Feb 14, 2005 #8
    how do u divide a fraction by a fraction? is all u do flip the denominator with the numerator or is there more?
     
  10. Feb 14, 2005 #9

    dextercioby

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    No.Compute this:(8:4):(12:6)=...?

    It's totally equivalent to:

    [tex]\frac{\frac{8}{4}}{\frac{12}{6}} [/tex]

    Daniel.
     
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