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Mass-Luminosity derivation help

  1. May 2, 2012 #1
    1. The problem statement, all variables and given/known data
    The main sequence lifetime of a star, T, is related to it's luminosity, L, in an equation of the form T[itex]\propto[/itex]L^-0.7
    Use this equation to derive the form of the mass-luminosity relation for main sequence stars.

    I know that I'm aiming for around L[itex]\propto[/itex]M^3.5

    Don't have a clue where to start, I know it'll be simple but I'm stuck.
    Any help is greatly appreciated. Thanks, Matt.
  2. jcsd
  3. May 3, 2012 #2


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    If a star has luminosity L, at what rate is it consuming energy? How much stored energy does it have? How is the lifetime related to these two quantities?
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