i am a little stuck on this, can someone please put me straight(adsbygoogle = window.adsbygoogle || []).push({});

This is from P7 of The Physics of Stars by AC Phillips

[tex]

g(r)=G m(r)/r^2

[/tex]

which states that each mass element at r moves towards the centre with an acceleration g(r). He then goes on to state that the inward velocity of the element can "be found from the conservation of energy equation."

[tex]

1/2 [ \frac {dr} {dt} ] ^2 = G m_o /r - G m_o /r_o

[/tex]

Now i know that both sides have been integrated but i thought the integral of

[tex]

\frac {d^2r} {dt^2} = \frac {dr} {dt}

[/tex]

forgive my tex errors :) the damn things buggy :0

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# Gravitational collapse help needed

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