XSIQ
*

Physics - Weightlessness

Weightlessness

An object is weightless if it experiences no force due to gravity. In
reality this is very rare. Even a satellite in orbit experiences a force
[1]due to gravity. It is this force that changes the direction of the
satellite's movement so that it circles the central body.

You are truly weightless at an infinite distance from other objects with
mass. [2] As your distance from other objects naive approaches infinity,
the force due to gravity approaches zero. In reality, it is not possible to
be an infinite distance from other objects with mass. Even in the space
between stars the gravitational fields [3] are strong enough to be
important for many calculations.

This galaxy is held together by gravitational forces between distant
stars

There is a place between any two planets where objects are effectively
weightless. At this place the gravitational fields of the planets are equal
in magnitude but opposite in direction. The gravitational fields [4] cancel
each other out to produce a net gravitational force [5] equal to zero.
There is a point between the moon and Earth where you are weightless
because the gravitational fields of the Earth and moon cancel each other
out.

Previous | Next

Links:
------
[1] http://alison.com/#
[2] http://alison.com/#
[3] http://alison.com/#
[4] http://alison.com/#
[5] http://alison.com/#