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Frames of reference & Inertial frames

  1. Mar 2, 2005 #1
    i've just started studying these but unfortunatley i've been unable to get my hands on the textbook, and my lecturer is... not that great :frown:

    Could somebody explain what these are to me? I have little to no idea about them as of now... maybe a few sample questions too? That would be a huuuuuge help.

    thanks in advance
  2. jcsd
  3. Mar 2, 2005 #2
    This deals with Special Relativity. Although it is also used in mechanics. For example, if a passenger is in a train, and there is a person outside the train watching it go by, then to the person outside the train, the passenger is moving in his frame of reference, while for the passenger, the train is not moving at all and the person standing outside the train is the one who is moving. The passanger inside the train is in the internal frame of reference. To each other, the other person is moving. Be careful though, neither person is wrong about their point of view. It is a little confusing once you get into Special Relativity, but this is a simple example.
    If you want to learn more, look search this topic on Goggle.


  4. Mar 2, 2005 #3

    Andrew Mason

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    A frame of reference is defined by a mass. All spatial points in the universe can be described as coordinates x,y,z relative to an origin at the mass' centre of mass. The time of events in the universe can be expressed as times as measured by a clock situated at the origin.

    An inertial frame of reference is a frame of reference defined by a mass that is not accelerating: ie there are no forces acting on it.

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