Accel Due to Gravity When Obj Touches Ground

In summary, when an object is standing on the ground, there is still an acceleration due to gravity acting on it, but it is canceled out by the normal force from the ground. This means that the net acceleration is zero, and the object does not continue to accelerate downwards.
  • #1
gracy
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if any object touches the ground i.e standing on the ground,will there be acceleration due to gravity?if yes,then how much more can object go downward due to this acceleration as it is already on the floor or ground?
 
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  • #2
The 'acceleration due gravity' is simply the force between two masses; in this case the object and Earth. When standing on the floor, floor provides the force in opposite direction according to Newton's 3rd law. But this force works on contact, so when falling in the air you accelerate towards the Earth.
 
  • #3
Brul said:
The 'acceleration due gravity' is simply the force between two masses; in this case the object and Earth. When standing on the floor, floor provides the force in opposite direction according to Newton's 3rd law. But this force works on contact, so when falling in the air you accelerate towards the Earth.
Brul said:
The 'acceleration due gravity' is simply the force between two masses; i
how can 'acceleration' be equal to force?
 
  • #4
gracy said:
if any object touches the ground i.e standing on the ground,will there be acceleration due to gravity?
I don't quite understand your question. If you are standing on the ground at rest, then you are not accelerating. This is because the net force on you would be zero: Your weight would be balanced by the supporting force of the ground.

Perhaps you can rephrase your question if I am missing your point.
 
  • #5
If you're falling from the sky or something it's because there is a force pulling between you and Earth -> Fgravitational = mobject*g'acceleration due gravity' and there is no opposite force stopping you (except friction of air). In dynamics (or at least in inertial systems) the only force that works remotely is gravity, others on contact. Thus when standing on the solid floor, they will exert an opposite force on you, so you won't sink in. Of course, Earth still pulls on you with the same force F=mg.
 
  • #6
Brul said:
When standing on the floor, floor provides the force in opposite direction according to Newton's 3rd law.
Careful here. The force provided by the floor is not a Newton's 3rd law pair with gravity. (It's Newton's 2nd law that is relevant here.)
 
  • #7
The the action reaction pair is gravity acting on m1 by m2, and the gravity acting on m2 by m1. A rule (not sure if it's actually a rule) that I have found very useful for Newton's 3rd Law is that the action reaction forces must be of the same type, i.e. gravitational and gravitational.

The actual answer to your question has already been stated several times, so I won't bother to reword it again, unless you want further clarification.
 
  • #8
"if any object touches the ground i.e standing on the ground,will there be acceleration due to gravity?"
yes, there is always an acceleration due to gravity; if there wasn't you would have no "weight"
If there was no acceleration due to gravity, when you go to stand on a scale, there would be no force pushing down on the scale, and thus, it would read "0"

Newton's second law states Force=mass*acceleration; Your weight is a force;

"If yes,then how much more can object go downward due to this acceleration as it is already on the floor or ground?"

If it is already on the floor or ground, it cannot go any further. That does not mean it isn't still "accelerating"

The force of your weight is canceled out by an opposite force from the floor; If you think about this logically, its obvious, as people don't just go falling through the ground; There is an equal and opposite force from the matter that the ground is made up of, pushing up against the force of your weight, and thus, balancing out all the forces to a net force of 0;
 
  • #9
Taimoor Qamar said:
If it is already on the floor or ground, it cannot go any further. That does not mean it isn't still "accelerating"

Actually, I would steer away from saying that you are accelerating. It could cause confusion. I believe the best definition for the OP is that the NET acceleration is zero, acceleration is a change in motion, because the forces cancel out, hence dv/dt (change in velocity over change in time) is zero.

Sorry to be nitpicky, especially if I'm actually wrong, just trying to avoid confusion for the OP.
 
  • #10
Taimoor Qamar said:
"if any object touches the ground i.e standing on the ground,will there be acceleration due to gravity?"
yes, there is always an acceleration due to gravity; if there wasn't you would have no "weight"
If there was no acceleration due to gravity, when you go to stand on a scale, there would be no force pushing down on the scale, and thus, it would read "0"
I would say that there is always a force of gravity, not necessarily an acceleration due to gravity.

Taimoor Qamar said:
Newton's second law states Force=mass*acceleration; Your weight is a force;
Best written as ##\Sigma F = ma## to emphasize that it's the net force that determines the acceleration.

Taimoor Qamar said:
If it is already on the floor or ground, it cannot go any further. That does not mean it isn't still "accelerating"
Sure it does. The acceleration is zero.

Taimoor Qamar said:
The force of your weight is canceled out by an opposite force from the floor; If you think about this logically, its obvious, as people don't just go falling through the ground; There is an equal and opposite force from the matter that the ground is made up of, pushing up against the force of your weight, and thus, balancing out all the forces to a net force of 0;
Good!
 
  • #11
The body always experiences g unless you are at the center of earth. Net acceleration maybe zero. It will try to pull you in. But the surface provides a normal force upwards. If you were to stand on a spring attached to Earth's centre you will start moving down.
 

1. What is acceleration due to gravity?

Acceleration due to gravity is the rate at which the velocity of an object changes as it falls towards the ground. It is caused by the gravitational pull of the Earth and has a constant value of 9.8 meters per second squared (m/s²).

2. How does acceleration due to gravity affect objects?

Acceleration due to gravity causes objects to fall towards the ground at a faster and faster rate. This means that the velocity of the object increases as it falls, resulting in a greater impact when it reaches the ground.

3. What factors affect acceleration due to gravity?

The main factor that affects acceleration due to gravity is the mass of the object. The greater the mass, the greater the gravitational pull and the faster the object will accelerate towards the ground. Other factors such as the distance from the center of the Earth and air resistance can also affect acceleration due to gravity.

4. What is the formula for calculating acceleration due to gravity?

The formula for acceleration due to gravity is a = g = GM/r², where a is the acceleration, g is the gravitational constant (9.8 m/s²), M is the mass of the Earth, and r is the distance from the center of the Earth to the object.

5. How does acceleration due to gravity change when an object touches the ground?

When an object touches the ground, it is no longer accelerating due to gravity. Instead, it experiences a sudden change in velocity as it comes to a stop. This change in velocity is known as the impact velocity and is determined by the height from which the object was dropped and the acceleration due to gravity.

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