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Homework Help: Homework - more of a survey

  1. Sep 12, 2006 #1
    For one of my homework questions, I need to ask 2 to 3 people a question regarding Newton, then write an essay on it.

    Newton's First Law states that an object will move with a constant velocity if nothing acts on it (but I'm sure you all knew that). This seems to contradict our everyday experience that a moving object comes to a rest unless something acts to keep it going. Does this everyday experience contradict Newton's First Law? If it does not, explain how this experience is consistent with Newton's First Law. If it does, explain why we bother to teach Newton's First Law anyways.
    This may be easy for some of you, it was for me, but I'm supposed to ask so any different variety of answers would be appreciated. :smile:
  2. jcsd
  3. Sep 12, 2006 #2

    Andrew Mason

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    It depends on what you mean by everyday experience. Every day seems to be the same length, so I am aware that the earth continues to rotate at the same speed. It does not slow down at all. Every year, the seasons occur at about the same time and every year has the same number of days. This tells me that the earth is not slowing down as it orbits the sun. I see the moon in the sky and I don't see any changes to the moon's period of rotation. So I don't see my every day experience contradicting Newton's first law (which is actually Galileo's, I think).

  4. Sep 12, 2006 #3


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    Everyday experience almost always includes fricton and/or air resistance. Those are forces acting upon the object.

    But anyone who's dropped a penny on the ground knows how far it can roll without slowing down.
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