Newton's Third Law: Equal Forces & Stationary Object?

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Newton's third law states that for every action, there is an equal and opposite reaction between two bodies. This means that while the forces exerted by body A on body B and vice versa are equal in magnitude and opposite in direction, they act on different bodies, causing each to move. If no other forces are acting on the system, the net force is zero, and the center of mass will either remain at rest or move at a constant velocity. The confusion arises from misunderstanding that Newton's third law applies to interactions between bodies, not the net forces acting on a single body. Thus, acceleration occurs only when there is an unbalanced force acting on a body.
Lim Y K
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The Newton's third law states that the force exerted by body A on body B is equal to the force exerted by Body B on Body A . In this case, isn't the object supposed to be stationary because equal forces are acting on both sides?
Can someone please explain to me . Thanks
 
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Which object?
 
Lim Y K said:
The Newton's third law states that the force exerted by body A on body B is equal to the force exerted by Body B on Body A . In this case, isn't the object supposed to be stationary because equal forces are acting on both sides?
Can someone please explain to me . Thanks

The force exerted on body A causes body A to move.
The force exerted on body B causes body B to move.
These are two different forces acting on two different bodies; Newton's third law says that they will be of equal magnitude and opposite direction.

Search this forum and google for "cart-horse paradox" for more detail.
 
Lim Y K said:
In this case, isn't the object supposed to be stationary because equal forces are acting on both sides?

If there are no other forces acting on A and B, then the net force on the system of A and B together is indeed zero. It has an important physical consequence: the center of mass of the system either remains at rest, or moves at constant velocity according to Newton's First Law.
 
Lim Y K said:
The Newton's third law states that the force exerted by body A on body B is equal to the force exerted by Body B on Body A . In this case, isn't the object supposed to be stationary because equal forces are acting on both sides?
Can someone please explain to me . Thanks
Newton's Third Law applies to the interaction between one body and another and not the sum of Forces on a single Body, which says that you need a net unbalanced force for acceleration to take place. That's Newton 1. Each of the forces acting on a body (say the strings pulling it and the table it rests on) will have equal and opposite reaction forces - the mass pushes down on the table with the same force as the table keeping the mass up (N3). The tension in the string is the same in both directions (N3) - whether or not the string is causing the mass to accelerate (N1).
 
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