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Newton's Laws-Practical Applications?

  1. Mar 16, 2013 #1
    Hello all!
    I recently read The Universe in Zero Words, a book about the history and influence of important equations. In it, it said that Newton's Laws have made possible the launching of spacecrafts and the construction of tall buildings.
    With the spacecrafts, I might guess that he was talking about the calculation of the trajectory (when used together with Newton's Universal Law of Gravitation), but I don't see how these Laws have helped in building tall buildings.
  2. jcsd
  3. Mar 16, 2013 #2


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    Two applications:

    Designing tall buildings to withstand the forces produced by earthquakes.
    The wind loads on tall buildings are calculated from Newton's laws applied to the air.
  4. Mar 16, 2013 #3
    Newton's laws of motion do not just apply to systems in motion. In particular, the 3rd law (action/reaction) applies to static structures. When I was in school, one of the required classes was "statics". The entire class involved analyzing the forces within physical structures such as bridges, buildings, cranes etc. Newton's 3rd law was invoked everywhere yet nothing was ever moving.

    Maybe we should not call it "Newton's third law of motion".
    Last edited: Mar 16, 2013
  5. Mar 17, 2013 #4


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    You have to be a bit sympathetic towards the author. He is selling a general idea and he has needed to stretch things a little bit in order to justify himself. He's not actually 'wrong' in his statement but it may not be very meaningful or relevant. My advice is not to hang your hopes of 'understanding Physics' on books like that one. If you are looking for errors in popular Science books you can find much worse than that statement, btw. Those books are for entertainment and not for learning good solid Science.
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