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A question posed in my calculus class

  1. Oct 17, 2006 #1
    During my calculus class yesterday we were learning about the simpler way of determining derivatives, but before that we were discussing arcs and parabolas and the such and eventually about if you fired a bullet up from the ground to the top of the empire state building and it had the correct velocity you could catch it easily. And so the topic shifted about the old penny myth about dropping it from the empire state building. My physics teacher says that the penny would not touch the ground because of the gravitational pull of the empire state building would draw it in to the side of the building. So this is the question i pose to you all, If one was to drop a penny would it be drawn to the empire state building. Conversely would it be true also with a ball of copper or some metal?
    thanks you for your time.:biggrin:
  2. jcsd
  3. Oct 17, 2006 #2


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    Oh surely your teacher is putting you on. The gravitational pull of the empire state building, or any building is so small compared to the earth's that you wouldn't see any change in the trajectory of a penny. Now the empire state building is "stepped back" at the top. I'm not at all sure you could throw a penny from a window at the top so that it would clear the building lower down, but that has nothing to do with the gravitational pull of the building.

    Oh, and we are talking about gravity, not magnetic force. What the object is made of is irrelevant, except that very dense objects will overcome air resistance better than light ones.
  4. Oct 17, 2006 #3
    Interesting idea about catching the bullet though.
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