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Physics Algebra Cancelling Help

  1. Feb 27, 2007 #1
    1. The problem statement, all variables and given/known data
    I need to know how to cancel terms in the equation Ve = sqrt 2(6.6742 x 10^-11 N m^2 / kg^2 (12.1kg))/0.106780959m

    2. Relevant equations

    Ve = sqrt 2(mu)/r

    Where r is the distance from the denter of the object to be escaped from, and mu is the Gravitational Constant multiplied by the mass of the object to be escaped from.

    3. The attempt at a solution

    I really have no idea where to start...
  2. jcsd
  3. Feb 28, 2007 #2
    if u know what the end units are supposed to be, you can ignore units while solving the problem and just add the proper units to your final answer.

    but if u do this, make sure all the units are consistent.
  4. Feb 28, 2007 #3


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    Staff Emeritus
    Science Advisor
    Gold Member

    You cannot cancel numbers.

    Solve your problem algebraically, until you have isolated the quantity you need. Then, finally, the LAST step you use the numbers given.

    You will need to post a better problem statement to get help.

    The approach suggested by Pakmingki, is a bad one. You would be much better off to let the units guide your algebra.
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