Inertial reference frame for 2&3 law

AI Thread Summary
The discussion clarifies that the 2nd and 3rd laws of motion are only valid in inertial reference frames. The first law establishes the context for the second law and defines inertial frames and momentum. The second law, which defines force, cannot be applied in non-inertial frames without introducing fictitious forces. There is a common misconception that the second law subsumes the first, but the first law is essential in its own right. Ultimately, the second law's application is strictly limited to inertial frames.
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Does the concept of Inertial reference frame also applicable for 2nd & 3rd law of motion?
 
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The 2nd and 3rd laws are only valid in inertial frames. One way to look at the first law is that it establishes the context for the 2nd law. The first law defines the concept of an inertial frame and defines the concept of momentum. The second law is also more definition than law; it defines the concept of force. The third law is a true scientific law.
 
D H said:
The 2nd and 3rd laws are only valid in inertial frames. One way to look at the first law is that it establishes the context for the 2nd law. The first law defines the concept of an inertial frame and defines the concept of momentum. The second law is also more definition than law; it defines the concept of force. The third law is a true scientific law.

since 2nd law contain the term of acceleration & inertial frame consider the constant velocity or non-accelerated approach.
so i think 2nd law apply in non-inertial frame instead of inertial frame. am i right?? or wrong??
clear me.
thanks
 
That the second law subsumes the first is a common mistake. Look at it this way: Newton was a very smart guy. Not just the smartest of his time, but possibly the smartest person of all time. He felt the first law was essential, that it is something more than just a special case of the second law.

And no, the second law only applies in an inertial frame. Fictitious forces must be introduced to make the second law appear to apply in a non-inertial frame.
 
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