- #1
Karagoz
In a physics test in a Norwegian website of a school book, it says following:
True or false?
(1) According to Newton's 3rd Law, the weight of a book that is on a table is just as big, but opposite the force on the book from the table (normal force). FALSE.
(2) According to Newton's 1st Law, the weight of a book that is on a table is just as big, but opposite the force on the book from the table (normal force). TRUE.
[Edited and corrected it, I think I should be more precise in translation].
Why is the first statement false?
According to the Newton's 3rd Law: For every action, there is an equal and opposite reaction. The statement means that in every interaction, there is a pair of forces acting on the two interacting objects. The size of the forces on the first object equals the size of the force on the second object.
So the size of the forces on the first object (the book) equals the size of the force on the second object (the table). Isn't the first statement just an example of the Newton's 3rd Law?
True or false?
(1) According to Newton's 3rd Law, the weight of a book that is on a table is just as big, but opposite the force on the book from the table (normal force). FALSE.
(2) According to Newton's 1st Law, the weight of a book that is on a table is just as big, but opposite the force on the book from the table (normal force). TRUE.
[Edited and corrected it, I think I should be more precise in translation].
Why is the first statement false?
According to the Newton's 3rd Law: For every action, there is an equal and opposite reaction. The statement means that in every interaction, there is a pair of forces acting on the two interacting objects. The size of the forces on the first object equals the size of the force on the second object.
So the size of the forces on the first object (the book) equals the size of the force on the second object (the table). Isn't the first statement just an example of the Newton's 3rd Law?
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