🚀 go-pugleaf

>You're nearly right. Acceleration actually just means a change in 
>one's velocity, direction is integral to velocity.
>While we are not actually accelerating towards the earth at 9.8m/s^2
>(m/s is a measure of velocity not acceleration). The gravity we feel
>is a force that would cause an acceleration of 9.8m/s^2 if we
>were allowed to fall.
>
>The acceleration due to gravity is independant of mass.
>
>Barry.

Acceleration is rate of change of velocity, not change in velocity.
F=ma. You are being pulled with a force F towards the centre of the earth 
(gravity) This is why you don't float away. The ground you are standing 
on is exerting a balancing force upwards, which is why you don't sink to 
the centre of the earth. You can see the effect of this balancing force 
if you stand on, say, a trampoline. When you stand on the trampoline, 
gravity pulls you towards the centre of the earth. At first the 
trampoline allows this and you move towards the ground. This stretches 
the springs at the edge, which try and move back to their origianl length 
with a force given by Hookes Law. Eventually an equilibrium is reached 
where the Hookes Law (Spring) force is balanced by the gravity force, and 
you stop moving. Heavier people cause the trampoline to sag more (the m 
in F=ma). So reconsidering the F=ma bit, you can see that while there is 
a net force on a body there will be an acceleration (if you jump out of 
an aeroplane, there is a large net force until you reach terminal 
velocity where gravity is balanced by friction- hence you plummet). If 
there is no net force then there is no acceleration -see the discussion 
about balancing (or reaction) forces above.

Nick