Identifying Newtonian force pairs

AI Thread Summary
Newtonian force pairs involve interactions between two objects where each exerts a force on the other. In the case of a bottle on a table, the weight force from the bottle to the Earth and the weight force from the Earth to the bottle are valid Newtonian pairs. However, the normal force exerted by the table on the bottle does not pair with the weight force, as they act on the same object. Instead, the normal force pairs with the force exerted by the bottle on the table, which can be understood through the electromagnetic interactions of their electrons. This discussion highlights the importance of identifying the correct objects involved in force interactions to apply Newton's Third Law accurately.
MBBphys
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Homework Statement


Hello,
Regarding the idea of Newtonian force pairs, imagine a bottle resting on a table:
Weight force exerted on bottle by Earth and normal contact force on bottle by table are not Newtonian force pairs because they are different types and act on the same object.
Weight force exerted on bottle by Earth and weight force exerted on Earth by bottle are Newtonian forces.

So what Newtonian force pair includes the normal contact force on bottle by table? While making my notes, this is what I did not understand.
Thanks :)

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The Attempt at a Solution


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MBBphys said:
So what Newtonian force pair includes the normal contact force on bottle by table?
Consider the same interaction from the table's perspective.
 
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Remember Newton's Third Law and apply it to the normal force. The table is exerting a normal force on the bottle, therefore...
 
The atoms that comprise solids have electron clouds which push on each other. So most such forces can be considered electromagnetic. One electron pushes and is pushed, creating a force pair.

The bottle's electrons push on the table's electrons and the table's electrons push on the bottle's electrons.

Electrons can also pull. The bottle has electron bonds that hold it together.
 
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MBBphys said:

Homework Statement


Hello,
Regarding the idea of Newtonian force pairs, imagine a bottle resting on a table:
Weight force exerted on bottle by Earth and normal contact force on bottle by table are not Newtonian force pairs because they are different types and act on the same object.
Weight force exerted on bottle by Earth and weight force exerted on Earth by bottle are Newtonian forces.

In the following, what are the two objects involved?
So what Newtonian force pair includes the normal contact force on bottle by table? While making my notes, this is what I did not understand.
Thanks :)

Homework Equations


N/A

The Attempt at a Solution


N/A
 
Jeff Rosenbury said:
The atoms that comprise solids have electron clouds which push on each other. So most such forces can be considered electromagnetic. One electron pushes and is pushed, creating a force pair.

The bottle's electrons push on the table's electrons and the table's electrons push on the bottle's electrons.

Electrons can also pull. The bottle has electron bonds that hold it together.
Thank you! I got it now :)
 
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