Action-Reaction forces and angles

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Discussion Overview

The discussion centers around the nature of action-reaction forces, specifically whether these forces can be exerted at different angles relative to each other while still being equal in magnitude and opposite in direction. Participants explore the implications of angles in the context of Newton's third law of motion.

Discussion Character

  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant questions if action-reaction forces can be exerted at different angles, suggesting that this might not be covered by the concept of "opposite direction."
  • Another participant seeks clarification on what is meant by "opposite angles," expressing confusion over how this differs from opposite directions.
  • A hypothetical example involving a ball and a ping pong paddle is presented to illustrate the angles at which forces are applied, raising the question of whether these angles can be considered opposite.
  • Some participants assert that the direction of the forces is what matters for action-reaction pairs, while the angles of the objects themselves are less relevant unless they affect the force direction.
  • One participant states that the angle between the forces in action-reaction pairs is always 180°, implying that they are opposite in angle.
  • A later post reiterates that the angle formed between the force vectors must be π, otherwise a third resulting vector force would arise.

Areas of Agreement / Disagreement

Participants express differing views on the relevance of angles in action-reaction forces, with some asserting that the angles must be opposite while others argue that the angles of the objects do not affect the action-reaction relationship. The discussion remains unresolved regarding the implications of angles in this context.

Contextual Notes

There are unresolved assumptions regarding the definitions of "opposite angles" and how they relate to the forces involved. The discussion also touches on the implications of force direction and the geometric relationships between force vectors.

Sundown444
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Now, I am sure we all know that objects and their action-reaction forces happen in terms of exerting forces at opposite directions but with the same magnitude. That said, I wish to ask: Do objects with action-reaction forces have their forces exerted in opposite angles as well as opposite directions?
 
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What do you mean by "opposite angles"? I can't see what you could mean by this that isn't covered by "opposite direction".
 
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Or I guess I am asking, more precisely, do objects with action-reaction forces have act be exerted at different angles from each other, or the same?
 
I still don't understand. Can you give an example of two things that are in opposite directions but not opposite angles, however you are defining this?
 
Say a ball is hit by a ping pong paddle. The paddle hits the ball at 45 degrees. But the top of the ball is hit, say at 90 degrees. Would the angles between these two objects not be opposite in angles, even though the parts pushing each other are the same direction?
 
Sundown444 said:
Say a ball is hit by a ping pong paddle. The paddle hits the ball at 45 degrees. But the top of the ball is hit, say at 90 degrees. Would the angles between these two objects not be opposite in angles, even though the parts pushing each other are the same direction?
The direction that the ball hits the paddle or the paddle hits the ball is not relevant. What is relevant is the direction of the force. It is the direction of the two forces that are equal and opposite. The angle of the ball doesn't enter into it at all.
 
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So the angle does not matter in action reaction forces, you say?
 
Sundown444 said:
So the angle does not matter in action reaction forces, you say?
The angle of the force matters. The angle of the ball or the paddle or whatever doesn't matter except insofar as it affects the angle of the forces
 
So, are the angles of the force opposite, or same, or different to each other?
 
  • #10
Sundown444 said:
So, are the angles of the force opposite, or same, or different to each other?
The angle between the 3rd law forces is 180°.
 
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  • #11
A.T. said:
The angle between the 3rd law forces is 180°.

Okay, just wanted to make sure. Thanks!
 
  • #12
Sundown444 said:
... Do objects with action-reaction forces have their forces exerted in opposite angles as well as opposite directions?
The angle formed between both force vectors must be always π, otherwise we will have a third resulting vector force.

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