| | Gravity Page - J R Stockton (Site not responding. Last check: 2007-10-10) |
 | | Consider an arbitrary point inside a uniformly-charged spherical surface, and consider both an arbitrary small element of charged area and that second element of area which is marked out by straight lines from the edge of the first area through the point to meet the sphere again on the opposite side of the point. |
 | | That on the probe, being inverse-square dependent on the mass within its current distance from the centre, with that mass being proportional to the cube of the radius, is proportional to the distance from the centre. |
 | | Let the distance of a moon from its planet be r, that of the planet from its Sun be R ; let the mass of the planet be m, and the mass of the Sun be M ; let the orbital speeds of moon and planet around their primaries be v and V. |
| www.merlyn.demon.co.uk /gravity-.htm (5709 words) |