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3.5: Problems

  • Page ID
    141608
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    1. Using existing models or a current model interior program, find the expected solar neutrino flux (i.e., the flux of 8B neutrinos) as a function of solar age from the zero age model to the present.
    2. What polytrope(s) would you use to describe the structure of the sun? How well do they match the standard solar model?
    3. Consider a gas sphere that undergoes a pressure-free collapse. Let the free-fall time for material at the surface R be \(\mathrm{t}_f\). Find the mass distribution for an isothermal sphere and polytropes with indices \(n\) of 3, and 1.5 at: \[\begin{array}{ll}
      \mathrm{a} & \mathrm{t}=0.1 \mathrm{t}_f, \\
      \mathrm{b} & \mathrm{t}=0.5 \mathrm{t}_f, \text { and } \\
      \mathrm{c} & \mathrm{t}=0.8 \mathrm{t}_f .
      \end{array}\nonumber\]

    4. Use the Virial theorem to find the fundamental radial pulsation period for a star where the equation of state is \(\mathrm{P}=\mathrm{Kp}^\gamma\). Find the behavior of this period as \(\gamma \rightarrow \infty\).
    5. Find the mass of a main sequence star for which the energy production by the p-p cycle equals that of the CNO cycle.

    This page titled 3.5: Problems is shared under a Public Domain license and was authored, remixed, and/or curated by George W. Collins II (Pachart Foundation) via source content that was edited to the style and standards of the LibreTexts platform.