Newton's laws and non inertial frame of reference

AI Thread Summary
Newton's laws do not hold in non-inertial frames because objects can accelerate without any external forces acting on them. To reconcile this, fictitious forces must be introduced, allowing Newton's laws to be applied, but complicating the system. These fictitious forces do not adhere to Newton's third law, leading to inconsistencies. Thus, while Newton's laws can be adapted for non-inertial frames, careful consideration is required. Ultimately, the laws remain valid but require adjustments to account for the complexities of acceleration.
raknath
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Hi all


Why do we actually say that Newton's laws do not hold for non inertial frames. can you folks give me an example of how Newton's laws collapse in an non inertial frame(if they do at all)
 
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raknath said:
Why do we actually say that Newton's laws do not hold for non inertial frames. can you folks give me an example of how Newton's laws collapse in an non inertial frame(if they do at all)

In accelerated frames objects with no forces acting on them accelerate. So you have to introduce "http://en.wikipedia.org/wiki/Fictitious_force" " to make Newtons laws work again.
 
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It's not that Newton's laws fail it's just that in a non-inertial reference frame one cannot consider their system to be 'free of external forces' and things get complicated. However, it can all be worked out using Newton's laws you just have to be very careful.
 
A.T. said:
In accelerated frames objects with no forces acting on them accelerate. So you have to introduce "http://en.wikipedia.org/wiki/Fictitious_force" " to make Newtons laws work again.
And the fictitious forces do not obey Newton's 3rd law, so in patching the 1st and 2nd laws that way the 3rd law doesn't work any more.
 
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