Newton's 2nd Law: F=ma - Does Object A Feel Force?

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Discussion Overview

The discussion revolves around the application of Newton's second law of motion, specifically the equation "F=ma," and whether an object (referred to as "A") feels a force when it encounters another object (referred to as "B") moving at a constant velocity. The scope includes conceptual understanding and the implications of force during collisions.

Discussion Character

  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions whether object "A" feels any force when it is struck by object "B," which is moving at a constant velocity, suggesting that since acceleration is zero, there may be no force felt.
  • Another participant explains that during a collision, the two objects exert forces on each other, leading to acceleration changes, although the duration of contact is typically very short.
  • A different viewpoint proposes that object "A" experiences an effective force calculated as m*v/t, where "m" is the mass of object "B," "v" is its velocity, and "t" is the time of contact.
  • One participant raises a concern about the direction of forces, noting that when "A" collides with "B," "A" accelerates in the opposite direction, prompting a question about how "B" also experiences force and begins to move with "A."
  • Another participant suggests that Newton's third law, which states that for every action there is an equal and opposite reaction, may provide insight into the interaction between the two objects.

Areas of Agreement / Disagreement

Participants express differing views on whether object "A" feels a force and how forces are transmitted during a collision. The discussion remains unresolved, with multiple competing perspectives presented.

Contextual Notes

Some assumptions about the nature of forces during collisions and the definitions of acceleration and contact time are not fully explored, leaving room for further clarification.

udar subedi
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in the Newtons second law of motion we study "F=ma" letters having their usual meanings.
so if any object say"A" comes in the way of a huge object "B", moving with a constant velocity; a=0, doesn't the object "a" feel any force upon him?
 
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When two objects collide, they are in contact for a while. At that time they exert a force on one another and they will accelerate (that is, one will decelerate and the other will accelerate, so in the end the moving one will go slower and the stationary one will be moving = going faster). The amount of time for which they are in contact is usually very short though. Also, we hardly ever need to know exactly how long it is, as problems involving colliding objects can usually be solved by looking at the (kinetic) energies before and after the collision.

Was that your question?
 
udar subedi said:
if any object say"A" comes in the way of a huge object "B", moving with a constant velocity; a=0, doesn't the object "a" feel any force upon him?

Object A will feel an effective force which is approximately equal to m*v/t

where,

m = mass of object B
v = velocity of object B
t = time of contact
 
that is pretty much an answer i had presumed.
But,force being a vector quantity has its effect in the direction in which an object accelerates. in the case, when "A" hits "B", "A" accelerates in opp. direction to "B", giving raise to a force in backward direction(the direction from which it is coming). Now how come "B" eperiences force and starts moving along with "A"?
 
The answer to your question is perhaps Newton's third law? Action - reaction
 

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