How does gravity work?
Definition: Gravity
The acceleration produced by the mutual attraction
of two masses, and of magnitude inversely proportional
to the square of the distance between the two
centers of mass.
Gravity is what causes things to have weight.
An objects mass remains constant, but its weight changes with
gravity, weight being the product of mass times
gravity. Astronauts in space appear to be weightless because
the gravity that far from the earth is negligible
(mass times almost zero = almost zero).
