Understanding Momentum: What Happens When Insufficient Force is Applied?

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Discussion Overview

The discussion centers around the concept of momentum and the effects of applying insufficient force to an object already in motion, specifically when attempting to accelerate a mass that is already moving at a significant fraction of the speed of light. Participants explore the implications of insufficient force on the object's acceleration and energy transfer.

Discussion Character

  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions what happens to the energy when an insufficient force is applied to an already moving mass, seeking clarification on whether it is absorbed, reflected, or dissipated.
  • Another participant asserts that applying any force will result in some acceleration, emphasizing that the energy is equal to the force times the distance.
  • A participant expresses a belief that a force must be sufficient to overcome inertia for acceleration to occur, indicating a potential misunderstanding of the relationship between force and acceleration.
  • Another participant challenges this belief, stating that any net force, regardless of its magnitude, will produce some acceleration, although it may be very small.
  • The discussion touches on the concept of static friction, suggesting that a greater force is needed to overcome static friction to initiate movement.

Areas of Agreement / Disagreement

Participants exhibit disagreement regarding the conditions under which a mass can accelerate when subjected to insufficient force. Some assert that any force will cause acceleration, while others maintain that a certain threshold must be met to overcome inertia.

Contextual Notes

There are unresolved assumptions regarding the definitions of force, inertia, and the specific conditions under which acceleration occurs. The discussion does not clarify the specific context of the forces being applied or the nature of the mass in question.

pallidin
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I can't seem to wrap my head around this. Perhaps you can help:

Let's say I've managed to accelerate a mass to 1/2c.
Now, I wish to get that mass going faster, BUT, the newly applied force is not enough to do this.

What then happens to the "insufficient" applied energy? Is it absorbed, reflected, dissipated, etc...?

Thanks
 
Last edited:
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What do you mean? If you apply a force the object will accelerate and the energy will be equal to the force times the distance.
 
Dale,

Thank you for your interest/reply.

If the force is unable to further accelerate the mass(by virtue of that force being weaker than required to overcome inertia) what happens to the applied force?

It is my understanding(perhaps wrong) that an applied force MUST be sufficient enough to overcome the inertia of the mass or the mass will NOT accelerate.
 
pallidin said:
It is my understanding(perhaps wrong) that an applied force MUST be sufficient enough to overcome the inertia of the mass or the mass will NOT accelerate.
This is a misunderstanding. Any net force, no matter how small, will result in an acceleration. If the force is very small relative to the mass then the acceleration will be correspondingly small, but it will still be there.

You may be thinking of static friction, where you have to apply a force greater than the static friction force in order for there to be a net force so that the object can start moving.
 
OK. Thank you so much.
 

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