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Inertial reference frame for 2&3 law

  1. Apr 20, 2010 #1
    Does the concept of Inertial reference frame also applicable for 2nd & 3rd law of motion?
     
  2. jcsd
  3. Apr 20, 2010 #2

    D H

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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.
     
  4. Apr 21, 2010 #3
    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
     
  5. Apr 21, 2010 #4

    D H

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    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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