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[Doubt] Newton's 3`rd Law

ok say if
Object A exerts a force on object B then object B exerts and equal and opposite force on object A.

So if i push a book resting on the table, then the force exerted by my push should be equal to the force of the book exerted on me. So nothing should happen, but infact that book moves forward whilst i remain stationary :s-smilie:. Why do anything in the world move if all the forces cancelled out with Newton's 3rd Law?
Reply 1
Avatar for Jex
Jex
OP
well? guys exam tomoro this question bugged me for yrs
if the book does move and you are stationary, you are not the only force acting on it. you must take into account friction, wind resistance etc. if you are pushing along a table, your putting a force on the book which is greater than the frictional force. if you push down on the book onto the table, the book wont go through the table as the force you push down with is exactly equal to the force the table is pushing back at you, so the book doesnt move.
Reply 3
Avatar for Willis123
Willis123
U r an idiot
Reply 4
Avatar for DarkWhite
DarkWhite
17
Use in relation to Newton's 2nd Law (essentially F=ma).

Just because the magnitude and directions of the resultant forces are equal and oppsite respectively, doesn't mean that you will both accelerate in opposite directions, because you have different masses. Also consider resistance to motion (air resistance, friction, etc).
Reply 5
Avatar for malolis
malolis
Newton's 3rd Law states that the every action has an equal and opposite reaction. This means that if a force is exerted on something it reacts with the same type of force. For example if you push on the book, it pushes back on your hand with the same force hence why your hand doesn't go through the book. There is still a resultant force on the book which pushes it forwards. It can push back on your hand and still move forwards.
Reply 6
Avatar for Jex
Jex
OP
Willis123
U r an idiot

lol?

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