Does Dropping an Object Increase the Force It Exerts on the Ground?

  • Thread starter Thread starter ag048744
  • Start date Start date
  • Tags Tags
    Mass
AI Thread Summary
Weight is defined as the force of gravity acting on an object, which creates a normal force when the object is at rest on a surface. When an object is dropped, it accelerates due to gravity until it reaches terminal velocity, where the force of gravity is balanced by air resistance. Upon impact, an impulsive force occurs, which is significantly greater than the weight of the object at rest, as it involves a rapid change in momentum. This impulsive force is temporary and results from the object's velocity just before impact. Ultimately, once the object settles, the forces return to being balanced, similar to the initial scenario.
ag048744
Messages
11
Reaction score
1
I have always known that weight is the force of gravity. Yet I have always been confused about one thing. If you hold up an object of mass and drop it, won't the ground experience a force that is greater than when the object just sits there?
 
Physics news on Phys.org
Yes' temporarily, but the force between the object and the ground is a contact force which has nothing to do with weight or gravity. You get a similar force whenever you lean against a wall, in which case the contact force isn't even vertical and clearly unrelated to your weight.
 
When the object just sits there on the surface of the Earth the force experienced by object onto the earth, and the Earth onto the object is equal and opposite in direction and it depends on the objects distance from the centre of the earth. The force of gravity causes the object to exert a force onto the earth, the Earth exerts an equal force opposite in direction on the object called the normal force. These two forces are balanced, therefore there is no net force, resulting in no acceleration.

When you set something into free fall from a certain height, it will accelerate toward the Earth based on the force of gravity and given enough time will reach terminal velocity due to drag, because the force of gravity will be balanced by the drag of the air on the object causing it to stop accelerating. When the object finally hits the earth, the force exerted temporarily onto the earth, will also be exerted by the Earth on the object, and will be based on the objects change of momentum required to provide the reverse acceleration settling it onto the surface of the earth. This force is called the impulsive force, a large force which occurs during collisions over a small period of time. After this impulsive force settles the object onto the Earth and ceases it from further accelerating, we return to the scenario in the first paragraph.

TLDR: Yes and the reason that the force experienced is greater on impact is because if the object was 1kg and traveling at 20 m/s, a force of 20 N will be exerted on it, in say one second, to bring it to 0 m/s. While just on the ground the object exerts a force of 9.8 N. This is the basic idea and my understanding of it.
 
Last edited:
Thread 'Question about pressure of a liquid'
I am looking at pressure in liquids and I am testing my idea. The vertical tube is 100m, the contraption is filled with water. The vertical tube is very thin(maybe 1mm^2 cross section). The area of the base is ~100m^2. Will he top half be launched in the air if suddenly it cracked?- assuming its light enough. I want to test my idea that if I had a thin long ruber tube that I lifted up, then the pressure at "red lines" will be high and that the $force = pressure * area$ would be massive...
I feel it should be solvable we just need to find a perfect pattern, and there will be a general pattern since the forces acting are based on a single function, so..... you can't actually say it is unsolvable right? Cause imaging 3 bodies actually existed somwhere in this universe then nature isn't gonna wait till we predict it! And yea I have checked in many places that tiny changes cause large changes so it becomes chaos........ but still I just can't accept that it is impossible to solve...
Back
Top