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===Corresponding Total Angular Momentum=== <table border="0" align="right" cellpadding="3"> <tr> <td align="center">'''Figure 2'''</td> </tr> <tr><td align="center"> [[File:EFE_AngMomVsEcc.png|center|350px|Maclaurin Spheroid Sequence]] </td></tr> <tr> <td align="center"> Solid black curve also may be found as: <div align="center"> Fig. 6 (p. 79) of [<b>[[Appendix/References#EFE|<font color="red">EFE</font>]]</b>];<br /> Fig. 7.3 (p. 174) of [<b>[[Appendix/References#ST83|<font color="red">ST83</font>]]</b>] </div> </td> </tr> </table> The total angular momentum of each uniformly rotating Maclaurin spheroid is given by the expression, <table border="0" cellpadding="5" align="center"> <tr> <td align="right"> <math>~L</math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~I \omega_0 \, ,</math> </td> </tr> </table> where, the moment of inertia <math>~(I)</math> and the total mass <math>~(M)</math> of a uniform-density spheroid are, respectively, <table border="0" cellpadding="5" align="center"> <tr> <td align="right"> <math>~I</math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~\biggl(\frac{2}{5}\biggr) M a^2 \, ,</math> </td> <td align="center"> and, </td> <td align="right"> <math>~M</math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~\biggl( \frac{4\pi}{3} \biggr) \rho a^2c \, .</math> </td> </tr> </table> Adopting the shorthand notation, <math>\bar{a} \equiv (a^2 c)^{1 / 3}</math>, we have, <table border="0" cellpadding="5" align="center"> <tr> <td align="right"> <math>~L^2</math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~ \frac{2^2 M^2 a^4}{5^2} \biggl[ A_1 - A_3 (1-e^2) \biggr] 2\pi G \biggl[ \frac{3}{2^2\pi} \cdot \frac{M}{a^2c} \biggr]</math> </td> </tr> <tr> <td align="right"> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~ \frac{6GM^3 {\bar{a}}}{5^2} \biggl[ A_1 - A_3 (1-e^2) \biggr]\biggl(\frac{a}{c}\biggr)^{4/3} </math> </td> </tr> <tr> <td align="right"> <math>~\Rightarrow ~~~ \frac{L}{(GM^3\bar{a})^{1 / 2}}</math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~ \frac{6^{1 / 2}}{5} \biggl[ A_1 - A_3 (1-e^2) \biggr]^{1 / 2}(1 - e^2)^{-1 / 3} \, .</math> </td> </tr> <tr> <td align="center" colspan="3"> [<b>[[Appendix/References#EFE|<font color="red">EFE</font>]]</b>], §32, p. 78, Eq. (7)<br /> [<b>[[Appendix/References#T78|<font color="red">T78</font>]]</b>], §4.5, p. 86, Eq. (54) </td> </tr> </table> <span id="MPT77angmom">This also means,</span> <table border="0" cellpadding="5" align="center"> <tr> <td align="right"> <math>L_*^2 \equiv \frac{L^2}{(GM^3\bar{a})}</math> </td> <td align="center"> <math>=</math> </td> <td align="left"> <math>\frac{6}{5^2} \biggl[ (3-2e^2)(1-e^2)^{1 / 2} \cdot \frac{\sin^{-1}e}{e^3} - \frac{3(1-e^2)}{e^2}\biggr](1 - e^2)^{-2 / 3} \, .</math> </td> </tr> <tr> <td align="center" colspan="3"> {{ MPT77 }}, §IVa, p. 591, Eq. (4.2) </td> </tr> </table> Figure 2 shows how the system's normalized angular momentum, <math>L_*</math>, varies with eccentricity along the Maclaurin spheroid sequence; given the chosen normalization unit, <math>~(GM^3\bar{a})^{1 / 2}</math>, it is understood that the mass and the volume — hence, also the density — of the configuration are held fixed as the eccentricity is varied. Strictly speaking, along this sequence the angular momentum asymptotically approaches infinity as <math>~e \rightarrow 1</math>; by limiting the ordinate to a maximum value of 1.2, the plot masks this asymptotic behavior. The small solid-green square marker identifies the location along this sequence where the system with the maximum angular velocity resides (see Figure 1); this system is not associated with a turning point along this angular-momentum versus eccentricity sequence.
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