Recent content by armin.hodaie

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    Orbit of Moon and the earth around thier COM

    the distances are not changing,they have the same distance from COM and from each other.both of them are rotating around COM with same angular velocity,so their distance won't change, go0d luck
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    Central forces in elliptic and parabolic orbits

    i won't write my workings here,and i think there is no one to help me.this forum is really weak,bye4ever
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    Central forces in elliptic and parabolic orbits

    dear BruceW, i have been trying for more than a week,but i can't solve them,so don't tell me that i haven't tried ! these are not simple problems :D bmp files are readible,but i will write down questions right now ! 1.if r and r1 are the radii vectors of two points C and C1 in a parabolic orbit...
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    Central forces in elliptic and parabolic orbits

    nobody?really?
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    Central forces in elliptic and parabolic orbits

    yes,this is homework.i have been trying to solve this two question for more than a week,but i can't solve it ;-(
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    Central forces in elliptic and parabolic orbits

    hi,can anyone solve this two problems?? these are from the "textbook on spherical astronomy" written by W.smart chapter five,problem number 18 and 19,Euler's theorem and Lambert's theorem thank you ;-)
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    Integral ∫dr/√((1/(R+r))-(1/R))

    no,i type it wrong ∫dr/√((1/(R+r))-(1/R))
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    Integral ∫dr/√((1/(R+r))-(1/R))

    Homework Statement ∫dr/√((1/(R+r))-(1/R)) Homework Equations The Attempt at a Solution
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    Undergrad Olbers Paradox and The Sherwood Forest

    hmmm,now i get it.thank you chrisas...i have been thinking on this problem for 3days ! wish U all the best
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    Undergrad Olbers Paradox and The Sherwood Forest

    i can't solve this problem...i can't understand how chrisas relate mean free path and this problem...would you mind solve this question completely? thank you very much
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    Understanding Angular Size Calculation: Europa and Jupiter

    assume that angular size of moon is "a" : tan (a)=(R1/D1) R1 : diameter of moon D1 : distance of moon-earth and for Jupiter that angular size is "b" : tan (b)=(R2/D2) R2 : diameter of jupiter----> R2=41R1 D2 : distance of jupiter-europa ----> D2=1.7D1 so we have: tan...
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    Second Year Physics Student's Guide to Self-Study: Lessons, Books, and More

    Of course i have the list,i want to know whether in other countries is different or not ! and also what books do you study in your UNI,maybe we are studying different books for the same course.i just wonder if there is better books for a specific course to study
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    Second Year Physics Student's Guide to Self-Study: Lessons, Books, and More

    hi,i am a second year student of physics. i want to know what do a second year student of physics should study?i mean what lessons,books,etc? our univercity professors can't teach well,and they make me CRAZY ! So i decided to study on my own...