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You have two same masses, one non-deformable and the other plastically deformable. You exert the same force for same time. Will they move with the same speed? Obviously the one will deform and move, while the other will only move.

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closed as off-topic by CuriousOne, Gert, user36790, ACuriousMind, Norbert Schuch Feb 6 '16 at 10:42

This question appears to be off-topic. The users who voted to close gave this specific reason:

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If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ Are there any other constraints (forces due to other interactions) on each mass? $\endgroup$ – Bill N Feb 5 '16 at 16:26
  • $\begingroup$ noooooooooooooo $\endgroup$ – ergon Feb 5 '16 at 22:06
  • $\begingroup$ I'm a bit surprised this got put on hold as homework like. It doesn't seem so to me. $\endgroup$ – John Rennie Feb 8 '16 at 7:20
  • $\begingroup$ @JohnRennie I have edited the question. Could it be reopened? Because in my opinion it is neither homework like, and no effort could really be taken by the OP... $\endgroup$ – FreezingFire Apr 29 '16 at 15:28
  • $\begingroup$ @FreezingFire: I have already voted to reopen the question, but it requires four additional reopen votes. I have no power to reopen this by myself. $\endgroup$ – John Rennie Apr 29 '16 at 15:42
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Newton's 2nd Law says that F=ma. This law says NOTHING about the physical properties of the object that you are accelerating. Thus, the answer is "yes", the two objects will accelerate at the same rate, so if they start at the same velocity, they will continue having matching velocities as long as they experience the same acceleration.

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  • $\begingroup$ "so if they start at the same velocity, they will continue having matching velocities as long as they experience the same acceleration." This feels like a cop-out, since the asker is implicitly questioning whether the accelerations will in fact be the same. Also, applying Newton's laws to real objects can work differently than applying them to theoretical "perfectly rigid" objects. $\endgroup$ – Asher Feb 5 '16 at 6:40
  • $\begingroup$ @Asher , fair enough. Watch the falling slinky youtube.com/watch?v=uiyMuHuCFo4 . The center of mass still accelerates downward at g, even though many parts of the slinky do not accelerate at all. $\endgroup$ – David White Feb 5 '16 at 11:58
  • $\begingroup$ a Slinky is elastic, though. The question is about plastic deformation. $\endgroup$ – Asher Feb 5 '16 at 12:21
  • $\begingroup$ Newton's 2nd Law says NOTHING about the physical properties of the object, but it ASSUMES point mass. $\endgroup$ – ergon Feb 5 '16 at 13:12
  • $\begingroup$ thank you Asher for asking the questions I would ask if I had seen this earlier $\endgroup$ – ergon Feb 5 '16 at 13:13

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