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common sense regarding the physical world

 
Nick George
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Say I have two perfectly circular "things" in an empty world. One has a mass of 2, the other has a mass of 1. Is there EVER an instance in which these two objects will collide, and the mass of 1 will have a resulting vector with a smaller magnitude than the mass of 2? This is occasionally happening in my program, which seems to me an indication that something's funky with my equations.
 
Warren Dew
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Yes.

Consider the case where both objects are moving in the same direction on the same path, the more massive one at a speed of 1, and the smaller one behind it and overtaking it with a speed of 4. After the collision, conserving momentum and kinetic energy, the small object will be motionless, and the large object will have accelerated to a speed of 3. (Both before and after, total momentum is 6, total kinetic energy 9.)
 
Nick George
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But if the smaller mass is still, then should it always end with a greater velocity?
 
Warren Dew
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By "Yes", I meant yes there is an instance in which these two objects will collide, and the mass of 1 will have a resulting vector with a smaller magnitude than the mass of 2 (in this example, the mass of 1 will have a resulting vector with a magnitude of 0).
 
fred rosenberger
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Joeseph,

are you asking

"If a 2kg object collides with a STATIONARY 1kg object, will the 1kg object ever have a smaller velocity?"

or, are you asking,

"a 1kg and 2kg object both have some initial non-zero velocity. is there some initial condition that will, after they collide, cause the 1kg object to have a smaller velocity than the 2kg?"
 
Arjun Shastry
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Joseph,are they projectiles?or just moving on plane surface?
 
Nick George
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sorry, been away a month.

so, I've refined my physics a bit, but it still feels a bit off. Would it be possible to post a zip file anywhere, that some interested party could try out and tell me if i'm just being paranoid?
 
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