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Importance of constants

  1. Aug 3, 2006 #1
    why should there is a 'constant' in a formula in which charactors on both sides are propotional to each other? and what should be the importance of it?:confused:
    Last edited: Aug 3, 2006
  2. jcsd
  3. Aug 3, 2006 #2
    Two quantities are said to be proportional when their ratio is a constant. If some variable y is proportional to another variable x, then their ratio, y/x, is a contant.

    y/x = k => y = kx. (k is some constant)
  4. Aug 3, 2006 #3
    im not sure that i understood ur question...
    are u asking what role constants play in pysical equations?

    because is u do, my answer is that those constants are there to keep all physical equations in the same unit system...

    lets take the niotonic equation on the gravitational force:
    this equation in principle is the same as : F=Mm/r^2.

    though such formation of the equation, will not give us the force in newtonic units, so we cannot compare this force to other known foces other than gravity...

    i hope i was clear though my crippled skills in english...
  5. Aug 3, 2006 #4


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    you can define units that get rid of these constants of proportionality. these are often called "natural units". check out:


    and take your pick of which constants to lose.
  6. Aug 3, 2006 #5

    it does not contradict with what i said.
    all i said that constants are there to keep a all physical properties in a certain system of units.

    ofcours u may use those "natural units", after all the newton unit was defined by multiplying our earthly gravity with mass.

    but u cannot compare two forces from different equalities of a property.
    if there is nothing to say, just say nothing, im annoyed that u just spill words without relating to what i wrote, maybe its because im tierd... no matter...
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