a) The comet released from rest at a distance rmax from the sun ( angular momentum =0 ). How long comet takes to reach the sun ? (take sun`s radius to be zero )(adsbygoogle = window.adsbygoogle || []).push({});

b) Assuming the comet can somehow pass freely through the sun describe its overal motion and find its period ?

I cant really think how to solve this problem , what I know it that since angular mom is zero, c=0 ( C= l^2/gama*reduced mass ,Gama=GMsMc)

so so if c=o c=rmax*(1-e) e=1 therefore Energy E=0 ( accually E=0 doesnt make sence eather since it has a PE = -Gmsmc/rmax ) so that is not a bonded orbit but parabolic orbit, But How can I use these to find the time ? the hint is use the technique t= integral dx/xdot where we find xdot from the Energy ( KE=mxdot/2=E-U(x) ) but I still dont understand how to use this since my understanding ( e=0 so E=0 )

please help, I would appreciate if anyone help. I still dont feel as if I completeley understood this subject but I have to turn the homework tomorrow :((

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# I dont know how to solve this problem

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