|MadSci Network: physics|
The force of gravity is computed as follows:
F = G(m1) (m2)/r2
G = Gravitational
Constant (G) =
meter^3 / kg-sec^2
m1 = Body of Mass #1
m2 = Body of Mass #2
r = Radial Distance between the two centers of mass
As can be seen, the force of gravity has to due with the mass of the bodies in question and the distance between their centers of mass.
Note: the above equation is in scalar form. The vector form is more descriptive, but also more complex. It requires an understanding of vector calculus. The pure form of the above equation is vector form; however, for this question, the scalar form is quite adequate.
[Moderator note: For the situation described the centripetal force between the person and the space station could be considered the weight of the person. This would go to zero if the person ran to counteract the spin of the station. The weight would increase if the person ran in the same direction as the spin. On a larger scale, the weightlessness of orbiting satellites is the result of the equivalence of gravitational acceleration and the centripetal acceleration required to remain in orbit.]
Try the links in the MadSci Library for more information on physics.