Why Do Objects Move Despite Equal and Opposite Reactions?

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Discussion Overview

The discussion revolves around the apparent contradiction in Newton's third law of motion, which states that for every action, there is an equal and opposite reaction. Participants explore why objects can still move despite this principle, focusing on the independence of objects and the application of forces in different contexts.

Discussion Character

  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions the understanding of Newton's third law, asking why movement occurs if every reaction is equal and opposite.
  • Another participant suggests that objects are independent of each other, using the example of pushing a box to illustrate that the box experiences an unbalanced force, leading to potential acceleration.
  • A different perspective is provided through the analogy of swimming, where kicking back against the water results in a forward motion due to the reaction force from the water, highlighting that forces act on different objects.
  • One participant emphasizes the importance of not confusing Newton's third law with the second law of motion, suggesting a need for clarity in understanding the laws.
  • Another reiterates that the forces involved are applied to different bodies, which may clarify the movement despite equal and opposite reactions.

Areas of Agreement / Disagreement

Participants express differing views on the interpretation of Newton's laws, particularly regarding the independence of objects and the nature of forces. There is no consensus reached on the initial question posed.

Contextual Notes

Some assumptions about the interaction of forces and the definitions of the laws of motion may not be fully articulated, leading to potential misunderstandings in the discussion.

Dirtyhand
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It says that every reaction there is a opposite and equal reaction. Why do things still move if everything is opposite and equal?
 
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Basically, objects are independent of each other, i think you are thinking of them as a system
Example: I push on a BOX. The box pushes back on ME. Something else does not push from the opposite side of the box to balance my push. The box experiences an unbalanced force and possibly accelerates.
 
to put it a different way, the forces act on different objects.
think of you swimming... you kick back your legs against the water, applying force on it by pushing it backwards, but by Newtons third law, the water will push back on you. The end result being that you get pushed forward by the water, and hence, move forward, and the water gets pushed back by your feet...
 
Dirtyhand said:
It says that every reaction there is a opposite and equal reaction. Why do things still move if everything is opposite and equal?

Don't confuse Newton's third law with the second.

http://en.wikipedia.org/wiki/Newton's_laws_of_motion
 
Dirtyhand said:
It says that every reaction there is a opposite and equal reaction. Why do things still move if everything is opposite and equal?

The forces are applied to different bodies.
 
Last edited:

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