Question #21. Isn't the answer Ta=1/2Tb (c)? The velocity for rocket A will be 2X faster than rocket B since mass A is 4 times mass B. If velocity A is greater then T=2(pi)r/v will be smaller for A than for B.

Manuel, you are absolutely correct - and the Word doc is correct, but evidently the open office text and the pdf file were never updated when this correction was made in 2016. I'll fix it now. Thank you for pointing this out. I solve this problem by using the expression T^3/r^2 = 4 pi^2/GM and ratioed it for case a and case b. Ratios are cool for these types of problems as everything cancels out except for the periods of A and B. John

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Benjamin Lieberman •7 months, 1 week ago • login to replyJohn Ennis •7 months, 1 week ago • login to replyManuel Tejelo •6 months, 3 weeks ago • login to replyJohn Ennis •6 months, 3 weeks ago • login to reply