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Inertial reference frames

  1. Feb 24, 2012 #1
    Hello, I am having difficulty understanding the concept of Newton's first law only applying in an inertial reference frame, or a frame that is at constant velocity, however, apparently the 1st law no longer applies if the reference frame is accelerating. Can anyone give me some sort of concrete example so I can see it in my mind, right now it's not making any sense to me. Actually, I just need an explanation of the whole concept of inertial vs noninertial reference frame.
    Last edited: Feb 24, 2012
  2. jcsd
  3. Feb 24, 2012 #2


    Staff: Mentor

    If you're floating out in space that's an inertial frame. If you toss a ball it will go straight at a constant velocity.

    In contrast a non-inertial frame is where you're standing on the earth and you toss a ball the ball travels in a curve.

    A pool table simulates an inertial frame in the xy plane ie z is height above the ground. Setting a ball in motion it will move straight and only slow due to friction.
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