Constant Acceleration Downwards

AI Thread Summary
Gravity exerts a constant force on objects, resulting in an acceleration of approximately 9.8 m/s² downwards. When standing still on the ground, the forces acting on the body are balanced, meaning there is no net acceleration despite the gravitational force. Thus, while gravity is always present, it does not cause acceleration unless there is a lack of support, such as when jumping or falling. The confusion arises from the distinction between the force of gravity and the actual state of motion. Understanding this concept clarifies that an object at rest is not accelerating downwards while in contact with a surface.
nate99
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I remember being taught that, due to gravity, we are always accelerating downwards. But how do you explain it?

Gravity is constant, and even if we are at rest, if I step on a scale I still get a weight of my mass X acceleration due to gravity. My forces vertically are balanced (me on the ground and the ground on me), therefore I have a constant velocity of no motion in the vertical direction.

But if I have no motion in the vertical direction then there is no change in velocity. I just stay at zero for velocity. So then how is my body ACCELERATING downwards? I completely understand that as soon as I jump or step off of a ledge and there is nothing to push up on me, my velocity will accelerate at 9.8 m/s2 in the down direction. But it's hard to understand how an object at rest is actually accelerating in the downward direction, unless I got my concepts mixed up, which often happens.

Thanks for the help!
 
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You aren't accelerating downwards while standing on the ground.
Gravity applies a force to your body, which would accelerate you at approximately 9.8 m/s2 if it could.
 
Drakkith said:
You aren't accelerating downwards while standing on the ground.
Gravity applies a force to your body, which would accelerate you at approximately 9.8 m/s2 if it could.

I see, I guess I just learned it wrong in the past. Thanks for correcting me
 
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