The discussion revolves around the implications and significance of Newton's Third Law, particularly exploring the hypothetical scenario of its absence. Participants examine the consequences of having no reaction forces in various contexts, including motion, force interactions, and the nature of forces themselves.
Participants generally do not reach a consensus, with multiple competing views on the implications of the absence of reaction forces and the significance of Newton's Third Law remaining unresolved.
Some arguments rely on assumptions about the nature of forces and interactions, and there are unresolved questions regarding the definitions and implications of force couples.
Is it not true that the wall is not moving because of frictional force between wall and the ground?dacruick said:Then Newton's Third Law would probably be "every force has no equal or opposite reaction force". but what is your question really. The significance to me of Newton's third law is that force is a kind of conservative value. It kind of governs motion. When you apply force to a wall, why doesn't the wall have an acceleration according to F=ma? Well that is because the wall is also applying the same force in the opposite direction, counter-acting your force. If there was no reaction force, the wall would have to move will acceleration F/m. I feel like I may not be answering your question though, would you like to be more specific?
bp_psy said:Nothing would happen because there would be absolutely NO forces.
Newtons three laws represent among other things a definition of force Couples. In the interaction of objects what arises is a force couple which is a thing in itself that is composed by 2 force vectors each acting on one of the 2 objects in the interaction.When doing problems it is sometimes useful to ignore one of the members of the couple but usually neglecting the other member is the mistake made most often.When thinking about the nature of the laws, thinking about only one member of the force is not useful and ultimately meaningless. What the interaction has created is the couple. If the interaction had not happened neither of the components would exist.And to this point no interaction has been observed that only created half a force couple. So the conclusion if the third law was not true then no forces would exist. This is my logic and there are probably more convincing and rigorous arguments out there.johncena said:Why no forces? I mean , what would happen if there is only action force,no reaction?
Your question has no answer.johncena said:I can't understand the significance of Newton's third law.
What would happen if there were no reaction forces?