Knowledge

Talk:Two-body problem

Source 📝

95: 1013:
i.e. minus the energy needed to escape the other if the other is kept in a fixed position; this should not be confused with the smaller amount of energy one body needs to escape, if the other body moves away also, in the opposite direction: in that case the total energy the two need to escape each other is the same as the aforementioned amount; the conservation of energy for each mass means that an increase of kinetic energy is accompanied by a decrease of potential energy, which is for each mass the inner product of the force and the change in position relative to the barycenter, not relative to the other mass
31: 85: 64: 264:
thumb are useful or explanatory, and they do not seem to be strongly organized. Finally, the topic of "two-body problem" is independent of the particular interaction potential between the two bodies; hence, rules of thumb specific to gravitation or to the Earth-Sun (or a hypothetical Sun-Sun) system seem not general enough for this article. Perhaps they would do better under
22: 1485:
Merge all three into a single article under the title "Two-body problem", with a popular introduction at the top and everything else at the bottom. Present the central force problem as a stepping stone to the full two-body problem, and make "Classical central-force" problem a redirect to that section
1421:
The rewrite was initially motivated by my own inability to easily find all the material on the problem from this article. In particular, this article presented a second-order differential equation that's at the center of the most important and interesting case, promised to show how to solve it... and
1235:
ellipse, its major and minor axes rotating slowly in the same sense as the oribital motion. The law of conservation of angular momentum still applies (Kepler's Second Law). Kepler's Third Law would in principle be altered slightly, but in practice, the only way to measure the sum of the masses is by
220:
P.S. If you find other physics articles that are too inscrutable, would you please let me know on my talk page? You shouldn't be shy about asking for more intelligibility. Sometimes it can't be helped; some topics are just hard to understand because they're so foreign to everyday life and also rely
1012:
formulas apply, with specific potential and kinetic energy and their sum taken as the totals for the system, divided by the reduced mass; the kinetic energy of the smaller body is larger; the potential energy of the whole system is equal to the potential energy of one body with respect to the other,
1311:
I think there should be added a sentence or two on the problem that sometimes is referred to als Two-body problem. I am however not really sure wether this sould be added to this page (the name is obviously derived from this one) or to make a redirection/disambiguation page. The last option however
1091:
year, the same as the orbital period of the Earth would be if the Sun would have twice its actual mass; the total energy per kg reduced mass (90 MJ/kg) is twice that of the Earth-Sun system (45 MJ/kg); the total energy per kg total mass (22.5 MJ/kg) is one half of the total energy per kg Earth mass
263:
The author seems to have intended this section mainly as a collection of rules of thumb for working with two-body problems. However, given that the general formulae are given in the earlier text, such rules of thumb do not seem to be needed. Moreover, it is not clear how these particular rules of
1211:
two-body problem. Therefore, it would seem to belong rather under the general theory of relativity, or under a more specific article about the motion of planets. It would be possible to cover the classical and GR gravitational two-body problems as illustrative examples in this article, but that
204:
I followed this link from another page, and from the first sentence, I was lost. I'm not a physicist or a scientist of any sort. Can someone who understands this stuff please write a layman's description for the first sentence? (I've noticed this happens a lot with physics-related articles, but
1294:
That's probably because the only two forces outside an object on a more than atomic scale are gravitational and electromagnetic, and they're both inverse square. However, if one object is allowed to get inside the other, the force exerted by the one in which the other is located is linear.
271:
Therefore, since the main points of this section were covered elsewhere (e.g., in the general formulae preceding this section), it seemed to help the flow of the article to eliminate this section and go straight to the explanatory examples. Thanks for your patience with me,
305:
Applying the gravitational formula we get that the position of the first body with respect to the second is governed by the same differential equation as the position of a very small body orbiting a body with a mass equal to the sum of the two masses, because
1339:
I think it is important to recreate the GIF animations so that they also include a colored side of a possible result of tidal force resulting from the two-body system, especially when referring to planet-satellite or planet-planet situations.
1376:
Newton's notation for the derivative with respect to time (the dots over the x in this article) is seldom enough used that many readers will be at a loss to determine its meaning. Leibniz's notation (dx/dt, dv/dt, etc.) may be preferable.
1203:
My reasons for deleting this section are slightly different. Here, the author points out an interesting correction of general relativity to the planetary motion expected from solving a classical two-body problem of gravity.
1257:, even when it deals only with algebra, is too technical to stand alone in an article. Perhaps someone who's invested in this article and has a strong understanding of the two-body problem can expound upon the topic... 1095:
at a distance of 2 AU (each following an orbit like that of the Earth around the Sun): the orbital period is 2 years, the same as the orbital period of the Earth would be if the Sun would have one quarter of its actual
1230:
gravity behaves somewhat differently, but, to a first approximation for weak fields, the effect is to slightly strengthen the gravity force at small separations. Kepler's First Law is modified so that the orbit is a
805: 221:
on lots of careful little definitions. But I'm sure that there are many others that need only a little help to make them clear. You could try some of the Physics articles mentioned on my User page; how about
1551: 1316:
Sometimes the term Two-body problem is used for the problem that it is hard two scientists which form a couple to both find a position at a distance which is such that they can still live together.
35: 245:. Please let me know if you like it as is, or if there are still confusing parts. I didn't tinker with the stuff at the very end; maybe someone else can decide whether it's worth keeping? 375: 872: 1132: 1089: 260:
I apologize for having deleted the section on "Newtonian gravity", but I hope that the following will explain my reasoning, and that everyone will agree that the article is improved.
1541: 630: 480: 1207:
This section, although covering a fascinating topic, does not seem at home in this article, since it is specific for the relativistic gravitational two-body problem, and not the
1468:
Rename "Classical central-force problem" to some more general title that makes it clear that it actually solves the general two-body problem, not just the central force problem.
1556: 1571: 932: 682: 209:
Yeah, I know :( I've been meaning to fix this article, but I've been busy with a few others lately. Why don't you check back in a few days? Thanks for being patient. :)
1172: 968: 991: 549: 522: 1034: 1462:
Update the "Classical central-force problem" article to cover any math that's in this article that it doesn't already cover, and remove that math from this article.
151: 1418:
I just did a pretty major rewrite of the overview parts of this article, trying to provide a general explanation of what's going on for more casual readers.
1422:
then didn't. The actual solution is in other articles with counterintuitive names that didn't have any described links, just general "see also" references.
1253:
This article needs more prose. It should be intelligible for those with and without expertise in math. Not that the math is necessarily so complicated, but
1536: 1566: 1478:, which is just a list of solutions without any explanation of how you get them, into one or the other article. I'm not sure which makes more sense. 141: 1546: 94: 1437:
looks to be most complete... but is misnamed, because it actually also covers the generalization to the full two-body problem. There's also
1509: 186:
After the section "Change of variables", the solving of the equation is not pursued. A detailed discussion on the subject may be found at
1425:
There's still a lot of work to do, and I'm not really qualified to do it. In particular, pretty much the same math is presented here, in
1490: 1399: 710: 415: 265: 117: 1561: 483: 283: 1531: 1434: 1426: 1471:
Replace the majority of math this article with a link to that article, and make the "Kepler problem" article a redirect to it.
1475: 1438: 1186: 108: 69: 1227: 44: 1236:
applying that Law as it stands, so there is effectively no change. These results were first obtained approximately by
309: 1513: 816: 1494: 1403: 1276:
It is unclear from the article what applications there are for the general solution to the two-body problem
1009: 1102: 1060: 1241: 191: 574: 430: 50: 1312:
would mean a page specified to the social problem while I guess one could suffice with something like:
1300: 1395: 1254: 1175: 938: 21: 889: 116:
on Knowledge. If you would like to participate, please visit the project page, where you can join
1459:
a general, mostly non-mathematical introduction, along the lines of what I've put into the intro.
1296: 1212:
would significantly increase the article's length. What does everyone think -- is it worth it?
635: 1148: 187: 1325: 222: 1378: 1343: 1285: 1262: 1134:
AU: the orbital period is 1 year, the same as the orbital period of the Earth around the Sun
999: 698: 943: 1237: 973: 527: 500: 408: 1019: 1430: 1054: 810: 705: 568: 287: 100: 1525: 694: 1441:, which gives solutions for the gravitational case but does not try to derive them. 1036:
is twice the semi-major axis times the absolute value of the specific orbital energy
1321: 1213: 1190: 1050:
the reduced mass is one half of the mass of one Sun (one quarter of the total mass)
1003: 273: 246: 226: 210: 300:
I reproduce the deleted section here, in case anyone would like to glean from it
1281: 1258: 84: 63: 1232: 291: 90: 697:; the same ratios apply for the velocities, and, without the minus, for the 1517: 1498: 1448:
Have two articles: split the math part from the popular part, but combine
1407: 1392:
I don't believe that the potential function U is defined in the article.
1366: 1329: 1289: 1266: 1216: 1193: 294: 276: 249: 229: 213: 194: 241:
Hi, rather than waiting, I decided to try my best at fixing the article
1465:
Also fold in anything that's missing from the "Kepler problem" article.
691: 113: 1221:
Here's the deleted text again, in case anyone wishes to glean from it
286:, so I added the a^3/T^2 = M formula there, and changed the link at 1045:
For example, consider two bodies like the Sun orbiting each other:
282:
Some text from the first half of what you deleted is replicated at
800:{\displaystyle rv^{2}=r^{3}\omega ^{2}=4\pi ^{2}r^{3}/T^{2}=\mu } 1145:
Similarly, a second Earth at a distance from the Earth equal to
393:
is the position of one body relative to the other (above called
284:
standard gravitational parameter#Two bodies orbiting each other
1320:(I have to agree that this sentence may be splitted or so). -- 15: 701:
with respect to the barycenter and for the kinetic energies
1240:, and the rigorous two body problem was later solved by 571:
applies; recalling that the positions of the bodies are
690:, respectively, we see that the two bodies' orbits are 1552:
Knowledge level-5 vital articles in Physical sciences
1151: 1105: 1063: 1022: 976: 946: 892: 819: 713: 638: 577: 530: 503: 433: 312: 112:, a collaborative effort to improve the coverage of 886:the total mass relative to that of the Sun, we get 1199:Deletion of "General Relativistic Gravity" section 1166: 1126: 1083: 1028: 985: 962: 926: 866: 799: 676: 624: 543: 516: 474: 369: 1542:Knowledge vital articles in Physical sciences 8: 1452:of the math into one comprehensive article. 1557:C-Class vital articles in Physical sciences 370:{\displaystyle m_{1}m_{2}/\mu =m_{1}+m_{2}} 205:this is the first time I've mentioned it.) 1572:C-Class physics articles of Mid-importance 1393: 58: 1280:for inverse-square laws like gravity. -- 1157: 1152: 1150: 1111: 1106: 1104: 1074: 1064: 1062: 1021: 975: 954: 945: 912: 903: 897: 891: 867:{\displaystyle 4\pi ^{2}a^{3}/T^{2}=\mu } 852: 843: 837: 827: 818: 785: 776: 770: 760: 744: 734: 721: 712: 648: 637: 613: 600: 588: 582: 576: 535: 529: 508: 502: 463: 450: 432: 361: 348: 333: 327: 317: 311: 256:Deletion of "Newtonian gravity" section 60: 19: 1444:I would suggest one of the following: 1127:{\displaystyle {\sqrt{2}}\approx 1.26} 1084:{\displaystyle {1 \over 2}{\sqrt {2}}} 7: 1455:Make the "Two-body problem" article 1414:Structural hackery done, more needed 1381:10:39, 27 January 2013 (US/Pacific) 106:This article is within the scope of 1016:for elliptic and hyperbolic orbits 625:{\displaystyle m_{2}/(m_{1}+m_{2})} 475:{\displaystyle \mu =G(m_{1}+m_{2})} 49:It is of interest to the following 1092:in the Earth-Sun system (45 MJ/kg) 416:specific relative angular momentum 14: 551:are the masses of the two bodies. 266:Kepler's laws of planetary motion 188:Eric Weisstein's world of physics 1537:Knowledge level-5 vital articles 486:(the sum of those for each mass) 484:standard gravitational parameter 288:Alpha Centauri#System components 93: 83: 62: 29: 20: 1567:Mid-importance physics articles 1435:Classical central-force problem 1427:Classical central-force problem 421:are defined accordingly (hence 146:This article has been rated as 1547:C-Class level-5 vital articles 1476:Gravitational two-body problem 1439:Gravitational two-body problem 1388:Laws of Conservation of Energy 1187:Gravitational two-body problem 671: 653: 619: 593: 469: 443: 1: 1367:21:11, 25 February 2012 (UTC) 927:{\displaystyle a^{3}/T^{2}=M} 126:Knowledge:WikiProject Physics 120:and see a list of open tasks. 1408:20:40, 18 January 2016 (UTC) 1290:07:42, 2 December 2008 (UTC) 1228:general theory of relativity 1174:times the usual distance of 195:12:07, 25 October 2005 (UTC) 129:Template:WikiProject Physics 1053:at a distance of 1 AU: the 677:{\displaystyle -m1/(m1+m2)} 295:16:16, 27 August 2006 (UTC) 1588: 1330:08:25, 25 March 2009 (UTC) 1303:) 18:47, 4 May 2009 (EDT) 1267:16:35, 24 April 2008 (UTC) 1217:07:38, 6 August 2006 (UTC) 1167:{\displaystyle {\sqrt{2}}} 277:07:22, 6 August 2006 (UTC) 152:project's importance scale 1307:"social" Tow-body problem 1194:13:03, 23 June 2007 (UTC) 970:is constant and equal to 250:19:43, 13 June 2006 (UTC) 230:16:44, 13 June 2006 (UTC) 225:? Thanks for your help! 214:16:44, 13 June 2006 (UTC) 145: 78: 57: 1562:C-Class physics articles 1499:19:47, 6 June 2019 (UTC) 1178:would be geosynchronous. 1518:17:30, 9 May 2024 (UTC) 1354:Ἑλλαιβάριος Ellaivarios 1010:specific orbital energy 1532:C-Class vital articles 1486:in the merged article. 1318: 1242:Howard Percy Robertson 1189:and am improving it.-- 1168: 1128: 1085: 1030: 987: 964: 963:{\displaystyle rv^{2}} 939:parabolic trajectories 928: 868: 801: 678: 626: 545: 518: 476: 371: 1314: 1176:geosynchronous orbits 1169: 1129: 1086: 1031: 988: 986:{\displaystyle 2\mu } 965: 929: 869: 802: 679: 627: 546: 544:{\displaystyle m_{2}} 519: 517:{\displaystyle m_{1}} 477: 372: 36:level-5 vital article 1255:mathematical physics 1149: 1103: 1061: 1029:{\displaystyle \mu } 1020: 974: 944: 890: 878:expressed in AU and 817: 711: 636: 575: 528: 501: 431: 310: 1372:Derivative notation 882:in years, and with 109:WikiProject Physics 1164: 1124: 1081: 1026: 983: 960: 924: 864: 797: 674: 622: 541: 514: 472: 367: 45:content assessment 1410: 1398:comment added by 1162: 1116: 1099:at a distance of 1079: 1072: 223:centripetal force 166: 165: 162: 161: 158: 157: 1579: 1433:. Of the three, 1364: 1362: 1360: 1358: 1356: 1173: 1171: 1170: 1165: 1163: 1161: 1153: 1133: 1131: 1130: 1125: 1117: 1115: 1107: 1090: 1088: 1087: 1082: 1080: 1075: 1073: 1065: 1035: 1033: 1032: 1027: 1000:angular momentum 992: 990: 989: 984: 969: 967: 966: 961: 959: 958: 933: 931: 930: 925: 917: 916: 907: 902: 901: 873: 871: 870: 865: 857: 856: 847: 842: 841: 832: 831: 806: 804: 803: 798: 790: 789: 780: 775: 774: 765: 764: 749: 748: 739: 738: 726: 725: 699:angular momentum 683: 681: 680: 675: 652: 631: 629: 628: 623: 618: 617: 605: 604: 592: 587: 586: 550: 548: 547: 542: 540: 539: 523: 521: 520: 515: 513: 512: 481: 479: 478: 473: 468: 467: 455: 454: 425:is the distance) 376: 374: 373: 368: 366: 365: 353: 352: 337: 332: 331: 322: 321: 134: 133: 132:physics articles 130: 127: 124: 103: 98: 97: 87: 80: 79: 74: 66: 59: 42: 33: 32: 25: 24: 16: 1587: 1586: 1582: 1581: 1580: 1578: 1577: 1576: 1522: 1521: 1506: 1504:To body problem 1416: 1390: 1374: 1352: 1350: 1348: 1346: 1344: 1337: 1309: 1274: 1251: 1201: 1147: 1146: 1101: 1100: 1059: 1058: 1018: 1017: 1002:divided by the 972: 971: 950: 942: 941: 908: 893: 888: 887: 848: 833: 823: 815: 814: 811:elliptic orbits 781: 766: 756: 740: 730: 717: 709: 708: 706:circular orbits 634: 633: 609: 596: 578: 573: 572: 531: 526: 525: 504: 499: 498: 459: 446: 429: 428: 409:semi-major axis 357: 344: 323: 313: 308: 307: 258: 238: 202: 184: 176: 171: 131: 128: 125: 122: 121: 99: 92: 72: 43:on Knowledge's 40: 30: 12: 11: 5: 1585: 1583: 1575: 1574: 1569: 1564: 1559: 1554: 1549: 1544: 1539: 1534: 1524: 1523: 1510:103.67.157.170 1505: 1502: 1488: 1487: 1482: 1481: 1480: 1479: 1472: 1469: 1466: 1463: 1460: 1431:Kepler problem 1415: 1412: 1389: 1386: 1384: 1373: 1370: 1336: 1333: 1308: 1305: 1273: 1270: 1250: 1247: 1246: 1245: 1223: 1200: 1197: 1185:I moved it to 1183: 1182: 1181: 1180: 1179: 1160: 1156: 1140: 1139: 1138: 1137: 1136: 1135: 1123: 1120: 1114: 1110: 1097: 1093: 1078: 1071: 1068: 1055:orbital period 1051: 1042: 1041: 1040: 1039: 1038: 1037: 1025: 1014: 1006: 993: 982: 979: 957: 953: 949: 935: 923: 920: 915: 911: 906: 900: 896: 863: 860: 855: 851: 846: 840: 836: 830: 826: 822: 807: 796: 793: 788: 784: 779: 773: 769: 763: 759: 755: 752: 747: 743: 737: 733: 729: 724: 720: 716: 702: 695:conic sections 673: 670: 667: 664: 661: 658: 655: 651: 647: 644: 641: 621: 616: 612: 608: 603: 599: 595: 591: 585: 581: 569:orbit equation 559: 558: 557: 556: 555: 554: 538: 534: 511: 507: 491: 490: 489: 488: 487: 471: 466: 462: 458: 453: 449: 445: 442: 439: 436: 426: 398: 379: 378: 364: 360: 356: 351: 347: 343: 340: 336: 330: 326: 320: 316: 302: 298: 297: 257: 254: 253: 252: 237: 234: 233: 232: 217: 216: 201: 198: 192:130.236.182.61 182: 181: 180: 175: 172: 170: 167: 164: 163: 160: 159: 156: 155: 148:Mid-importance 144: 138: 137: 135: 118:the discussion 105: 104: 101:Physics portal 88: 76: 75: 73:Mid‑importance 67: 55: 54: 48: 26: 13: 10: 9: 6: 4: 3: 2: 1584: 1573: 1570: 1568: 1565: 1563: 1560: 1558: 1555: 1553: 1550: 1548: 1545: 1543: 1540: 1538: 1535: 1533: 1530: 1529: 1527: 1520: 1519: 1515: 1511: 1503: 1501: 1500: 1496: 1492: 1484: 1483: 1477: 1473: 1470: 1467: 1464: 1461: 1458: 1454: 1453: 1451: 1447: 1446: 1445: 1442: 1440: 1436: 1432: 1428: 1423: 1419: 1413: 1411: 1409: 1405: 1401: 1397: 1387: 1385: 1382: 1380: 1371: 1369: 1368: 1365: 1355: 1341: 1334: 1332: 1331: 1327: 1323: 1317: 1313: 1306: 1304: 1302: 1298: 1292: 1291: 1287: 1283: 1279: 1271: 1269: 1268: 1264: 1260: 1256: 1249:Too technical 1248: 1243: 1239: 1234: 1229: 1225: 1224: 1222: 1219: 1218: 1215: 1210: 1205: 1198: 1196: 1195: 1192: 1188: 1177: 1158: 1154: 1144: 1143: 1142: 1141: 1121: 1118: 1112: 1108: 1098: 1094: 1076: 1069: 1066: 1056: 1052: 1049: 1048: 1047: 1046: 1044: 1043: 1023: 1015: 1011: 1007: 1005: 1001: 998:is the total 997: 994: 980: 977: 955: 951: 947: 940: 936: 921: 918: 913: 909: 904: 898: 894: 885: 881: 877: 861: 858: 853: 849: 844: 838: 834: 828: 824: 820: 812: 808: 794: 791: 786: 782: 777: 771: 767: 761: 757: 753: 750: 745: 741: 735: 731: 727: 722: 718: 714: 707: 703: 700: 696: 693: 689: 688: 668: 665: 662: 659: 656: 649: 645: 642: 639: 614: 610: 606: 601: 597: 589: 583: 579: 570: 566: 565: 564: 563: 561: 560: 553: 536: 532: 509: 505: 497: 496: 495: 494: 492: 485: 464: 460: 456: 451: 447: 440: 437: 434: 427: 424: 420: 417: 413: 410: 406: 402: 399: 396: 392: 391: 386: 385: 384: 383: 381: 380: 362: 358: 354: 349: 345: 341: 338: 334: 328: 324: 318: 314: 304: 303: 301: 296: 293: 289: 285: 281: 280: 279: 278: 275: 269: 267: 261: 255: 251: 248: 244: 240: 239: 235: 231: 228: 224: 219: 218: 215: 212: 208: 207: 206: 199: 197: 196: 193: 189: 178: 177: 173: 169:External link 168: 153: 149: 143: 140: 139: 136: 119: 115: 111: 110: 102: 96: 91: 89: 86: 82: 81: 77: 71: 68: 65: 61: 56: 52: 46: 38: 37: 27: 23: 18: 17: 1507: 1491:76.10.176.53 1489: 1456: 1449: 1443: 1424: 1420: 1417: 1400:98.201.153.4 1394:— Preceding 1391: 1383: 1375: 1353: 1342: 1338: 1319: 1315: 1310: 1293: 1277: 1275: 1252: 1220: 1208: 1206: 1202: 1184: 1004:reduced mass 995: 883: 879: 875: 686: 685: 552: 422: 418: 411: 404: 400: 394: 389: 388: 299: 270: 262: 259: 242: 203: 185: 179:Heading text 147: 107: 51:WikiProjects 34: 1379:Kent Heiner 1335:TIDAL FORCE 387:the vector 236:Yuh huh! :D 1526:Categories 1278:other than 1272:Generalize 1233:precessing 414:, and the 1429:, and in 39:is rated 1396:unsigned 1322:yanneman 1238:Einstein 382:Assume: 1226:In the 1209:general 1191:Patrick 692:similar 493:where: 247:WillowW 227:WillowW 211:WillowW 150:on the 123:Physics 114:Physics 70:Physics 41:C-class 1474:Merge 1297:Sslong 1282:Beland 1259:ask123 1214:Willow 874:(with 684:times 562:Then: 482:, the 407:, the 274:Willow 183:===== 47:scale. 292:Paddu 290:. -- 28:This 1514:talk 1495:talk 1457:just 1404:talk 1326:talk 1301:talk 1286:talk 1263:talk 1122:1.26 1096:mass 1008:the 937:for 809:for 704:for 632:and 567:the 524:and 200:Huh? 1450:all 1057:is 243:now 190:. 142:Mid 1528:: 1516:) 1508:1 1497:) 1406:) 1377:-- 1328:) 1288:) 1265:) 1119:≈ 1024:μ 981:μ 862:μ 825:π 813:: 795:μ 758:π 742:ω 640:− 435:μ 403:, 339:μ 268:? 1512:( 1493:( 1402:( 1363:_ 1361:_ 1359:_ 1357:_ 1351:_ 1349:_ 1347:_ 1345:_ 1324:( 1299:( 1284:( 1261:( 1244:. 1159:3 1155:2 1113:3 1109:2 1077:2 1070:2 1067:1 996:h 978:2 956:2 952:v 948:r 934:) 922:M 919:= 914:2 910:T 905:/ 899:3 895:a 884:M 880:T 876:a 859:= 854:2 850:T 845:/ 839:3 835:a 829:2 821:4 792:= 787:2 783:T 778:/ 772:3 768:r 762:2 754:4 751:= 746:2 736:3 732:r 728:= 723:2 719:v 715:r 687:r 672:) 669:2 666:m 663:+ 660:1 657:m 654:( 650:/ 646:1 643:m 620:) 615:2 611:m 607:+ 602:1 598:m 594:( 590:/ 584:2 580:m 537:2 533:m 510:1 506:m 470:) 465:2 461:m 457:+ 452:1 448:m 444:( 441:G 438:= 423:r 419:h 412:a 405:v 401:r 397:) 395:x 390:r 377:. 363:2 359:m 355:+ 350:1 346:m 342:= 335:/ 329:2 325:m 319:1 315:m 174:= 154:. 53::

Index


level-5 vital article
content assessment
WikiProjects
WikiProject icon
Physics
WikiProject icon
icon
Physics portal
WikiProject Physics
Physics
the discussion
Mid
project's importance scale
Eric Weisstein's world of physics
130.236.182.61
12:07, 25 October 2005 (UTC)
WillowW
16:44, 13 June 2006 (UTC)
centripetal force
WillowW
16:44, 13 June 2006 (UTC)
WillowW
19:43, 13 June 2006 (UTC)
Kepler's laws of planetary motion
Willow
07:22, 6 August 2006 (UTC)
standard gravitational parameter#Two bodies orbiting each other
Alpha Centauri#System components
Paddu

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.