Although there's equal and opposite reaction, usually the force is not balanced
Can you explain why?
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2What do you mean by ''the force is not seen balanced'' ? – AlmostClueless Jul 16 '20 at 15:14
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The forces act on different bodies, not on the same body – Jul 16 '20 at 15:14
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2see this post – Jul 16 '20 at 15:16
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3Does this answer your question? Given Newton's third law, why are things capable of moving? – Dale Jul 16 '20 at 15:19
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Needs context or specific details to answer effectively. – JAlex Jul 16 '20 at 18:19
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As mentioned in the post that is linked a couple of times above (which you should definitely read), it is the resultant force [obtained by vectorally adding all the forces acting] on a body that determines its motion. If I push a book across a horizontal table, I only need to consider the horizontal force I am applying and the frictional force of the table in the horizontal.
To get the book moving, I need to exert a force greater than the static frictional force. Once the book is moving, Newton's first law states that if my horizontal force and the dynamic frictional force match, then the book moves at a constant velocity. If I exert a greater force than the dynamic friction force, the book will accelerate.
Now horizontal forces on me would be that exerted by the book (equal and opposite to mine on the book) and the force of friction between my shoes and the floor. As long as the latter is larger than the former, I'll stay stationary as I push the book.
A quote from Mechanics 3rd edition, by Symon:
In applying Newton's law of motion, it is essential to decide first to what body the law is to be applied, then to insert the mass m of that body and the total force F acting on it. Failure to keep in mind this rather obvious point is the source of many difficulties, one if which is illustrated by the horse-and-wagon dilemma. A horse pulls upon a wagon, but according to Newton's third law the wagon pulls back with an equal and opposite force upon the horse. How then can either the wagon or the horse move?
Answer: to find the motion of the wagon, you need to look at the total force acting on it. You do not need to consider forces acting on the horse.
CGS
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