We have already seen that all objects fall with the same acceleration, 9.8 m/s/s (which we approximate as nearly 10 m/s/s).
We call this free fall.
When such objects fall, the only force acting on them is their weight, the force of gravity.
The only force on a body in freefall is the force of gravity. We call this its weight.
Since it accelerates at 9.8 m/s/s,
that weight must be
w = (mass)x(9.8 m/s/s),
w = mg
The weight of an object is the force of gravity on that object.
Weight, since it is a force, will be measured in units of newtons (N).
Mass will be measured in kilograms (kg).
F = m a Third Law Return to ToC, Newton's Laws of Motion (c) 2005, Doug Davis; all rights reserved