Why Is the Electromagnetic Force of the Table on the Book Considered Negligible?

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The discussion centers on the electromagnetic forces at play between a book and a table, specifically addressing why the electromagnetic force of the table on the book is considered negligible. It is established that while the book exerts an electromagnetic force on the table, the table also exerts an equal and opposite force on the book, which is not negligible as it supports the book's weight. The conversation highlights the action/reaction force pairs, emphasizing that the gravitational forces between the Earth and the book are negligible due to the Earth's mass, but the electromagnetic interactions at the molecular level are significant in maintaining the book's position on the table.

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briton
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A book on a table.
the gravitational force of attraction of the bookon the Earth is negligible...

if the reaction force is the electromagnetic force of repulsion of the book on the table, then why is the electromagnetic force of the table on the book negligible??
 
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briton said:
A book on a table.
the gravitational force of attraction of the bookon the Earth is negligible...
The action/reaction force pair is this: The Earth exerts a gravitational force on the book, and the book exerts and equal (but opposite) gravitational force on the earth. (Of course, the effect of that force on the massive Earth is negligible.)


if the reaction force is the electromagnetic force of repulsion of the book on the table, then why is the electromagnetic force of the table on the book negligible??
Now you are talking about a different set of forces: The book pushes on the table (electromagnetic forces involved) and thus the table pushes on the book with an equal force. The force on the book is not negligible--after all, it's what's holding the book up!
 
Doc Al said:
The action/reaction force pair is this: The Earth exerts a gravitational force on the book, and the book exerts and equal (but opposite) gravitational force on the earth. (Of course, the effect of that force on the massive Earth is negligible.)



Now you are talking about a different set of forces: The book pushes on the table (electromagnetic forces involved) and thus the table pushes on the book with an equal force. The force on the book is not negligible--after all, it's what's holding the book up!
sorry, I meant the electromagnetic force of the book on the table - this isn't negligible is it? It is of the same magnitude, but in an opposite direction to the force of the table on the book. mm I guess wht I really want to know, is what's happening on the ionic/molecular level... how is the table pushing with an electromagnetic/static force and how is the book pushing back?
 
Isn't it that the electrons of the book's molecules are close enough to the electrons of the table's molecules to provide sufficient repulsive force to keep the book afloat? (They're not really touching!)
 

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