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I know that in inertial ( stationary) frames conservation of momentum is a statement that sum of momentum before and after collision is same but what about moving frames? Particularly, accelerating ones?

Would there be a way to change the impulse equation so that it works in such frames? $$\Delta p =\int F * dt$$

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Newton's laws obey Newtonian relativity (often called Galilean relativity, but Galileo's statement was not precise and applies equally to Einstein's relativity. Newton's statement was precise). Consequently uniform motion makes no difference to conservation of momentum in Newtonian mechanics.

For an accelerating frame, the inertial force (pseudo force) integrated over time will change momentum. But in collision the amount of time is negligible, so the effect of the inertial force on conservation of momentum in collision would usually be regarded as negligible, meaning that conservation of momentum still holds.

Charles Francis
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  • Could you supplement the pseudo force case with an example? I'm having a bit difficulty with it. Thank you :) – tryst with freedom Apr 23 '20 at 09:47
  • If the time interval is vanishingly small for the integral you gave then so is the impulse. Otherwise you can include a term like this, but you may be better to work in an inertial frame. – Charles Francis Apr 23 '20 at 10:01
  • I feel like I can't get a context of that like can you give a situation describing what you said as an example? – tryst with freedom Apr 23 '20 at 10:19