Constant Acceleration Downwards

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SUMMARY

The discussion clarifies the concept of constant acceleration due to gravity, specifically addressing the misconception that an object at rest is accelerating downwards. Gravity exerts a force of approximately 9.8 m/s² on objects, but this force is counteracted by the normal force from the ground when standing still. Therefore, while gravity applies a downward force, it does not result in acceleration unless the object is in free fall. This distinction is crucial for understanding the principles of physics related to motion and forces.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Basic knowledge of gravitational force and acceleration
  • Familiarity with the concept of normal force
  • Knowledge of kinematics and free fall
NEXT STEPS
  • Study Newton's Second Law of Motion in detail
  • Explore the concept of free body diagrams to visualize forces
  • Learn about kinematic equations for uniformly accelerated motion
  • Investigate the effects of gravity on different objects in free fall
USEFUL FOR

Students of physics, educators explaining gravitational concepts, and anyone interested in understanding the principles of motion and forces in everyday scenarios.

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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