Can different forces cancel themselves?

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Discussion Overview

The discussion revolves around the concept of force cancellation in physics, particularly focusing on whether different non-parallel forces can cancel each other out when applied to an object. Participants explore theoretical scenarios, practical experiments, and the underlying principles of vector addition in this context.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants question whether three different pulling forces can cancel each other out, especially when applied to a "perfect object" with no dimensions.
  • There is a suggestion that any slight advancement observed in an experiment with a non-perfect object could be due to material imprecision.
  • One participant emphasizes the need to add the force vectors to determine cancellation, while another seeks to understand the reasoning behind cancellation despite the forces being different.
  • It is noted that for two forces to cancel, they must have the same magnitude but opposite directions, while three forces can have various combinations that result in a zero net force.
  • Another participant explains that if three forces sum to zero, they can be represented geometrically as a triangle when laid out head to tail, and similarly for four forces forming a quadrilateral.
  • One participant mentions that driving a car at constant velocity implies that the forces acting on it sum to zero, indicating a practical application of the concept.

Areas of Agreement / Disagreement

Participants express differing views on the nature of force cancellation, with some focusing on the mathematical aspects of vector addition while others emphasize practical implications. The discussion remains unresolved regarding the nuances of how different forces can cancel each other.

Contextual Notes

Participants do not fully agree on the conditions under which different forces can cancel, and there are references to potential factors such as friction that may affect the outcomes of practical experiments.

Pauly Denino
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If for say, I had a ''perfect object'' (Only mass with no dimensions) and I put three non-parallel and different pulling forces on the item, would these cancel themselves? After the doing the experiment myself with a non-perfect item, it seemed there was a slight advancement. The addition of the vectors gave me a near 0N force.

My questions are, is that slight advancement only due to the imprecision of my material and why do the forces cancel even thought they're all different?
 
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Pauly Denino said:
If for say, I had a ''perfect object'' (Only mass with no dimensions) and I put three non-parallel and different pulling forces on the item, would these cancel themselves? After the doing the experiment myself with a non-perfect item, it seemed there was a slight advancement. The addition of the vectors gave me a near 0N force.

My questions are, is that slight advancement only due to the imprecision of my material and why do the forces cancel even thought they're all different?

Making it even simpler, if you had an object with just one force acting on it, you can apply an equal and opposite force to cancel that force, correct?
 
Just add the force vectors. You know what a vector is?
 
I already added them, my questions is more towards the why the cancellation happens even thought the forces are different
 
If the vectors don't cancel, then the forces don't cancel. It's as simple as that. But maybe there is some friction that you haven't taken into account.
 
Pauly Denino said:
I already added them, my questions is more towards the why the cancellation happens even thought the forces are different
It's a little hard to understand your problem. The forces can cancel because they are different. If they were identical (in magnitude and direction) they effects will add up and you cannot have cancellation.

For two forces they should have same magnitude but opposite directions. For three forces you can have many possibilities, many combinations of magnitudes and directions which will give a zero resultant.
 
Pauly Denino said:
I already added them, my questions is more towards the why the cancellation happens even thought the forces are different
If you have three forces that sum to zero then if you lay them out head to tail then you will get a triangle. You can also get four forces to cancel if you lay then head to tail and you get a quadrilateral. Any number of vectors that takes you in a closed loop when laid end to end results in 0 net force.
 
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Thanks for you answers, they really helped me make my mind under the concept. I will definitely be using this website more often.
 
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Any time you drive a car at a constant velocity the forces on it sum to zero (aka cancel out).
 

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