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Homework Help: A question on constants and dimensionless equations

  1. Aug 18, 2012 #1
    1. The problem statement, all variables and given/known data

    There is not really a problem, just a question which i am about to ask. The known data is

    [tex]\alpha[/tex] the fine structure constant
    [tex]\hbar[/tex] Plancks constant
    [tex]c[/tex] the speed of light
    [tex]\mu[/tex] permeability

    2. Relevant equations

    [tex]2\alpha \hbar = \pi^2 \mu_0 c[/tex]

    3. The attempt at a solution

    A paper I downloaded a while back, but can't actually link to states this equation

    [tex]2\alpha \hbar = \pi^2 \mu_0 c[/tex]

    in a derivation. It seemed a little odd, are the dimensions right? I noticed all the data in this equation are actually made up of constants. Is it wise to say that when you deal with dimensionless objects, they are always constants (for a seperate question).
    Thank you!!!
  2. jcsd
  3. Aug 18, 2012 #2

    rude man

    User Avatar
    Homework Helper
    Gold Member

    No. For example, angles are dimensionless.
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