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Homework Help: Theory question

  1. Mar 21, 2005 #1
    i have a question where it asks me to find the uncertainty in a ball's postion (m=50g). i have that part all figured out, but then it asks me what the answer indicates about the relevance of quantum mechanics to macroscopic objects. (the answer was approx. 10^-32m, a very small uncertainty). i am having troubles understanding this. i'm not sure what to do. i know that HUP in general says that we can't know with certainty both the position and momentum of a particle at the same time, and the equation
    (delta x)(delta p) >h/4pi.

    i'm not sure where to go with this. any advice?
     
  2. jcsd
  3. Mar 21, 2005 #2

    dextercioby

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    What's the typical range of macroscopic objects...?In "m".Compare that value with the uncertainty u found...

    Daniel.
     
  4. Mar 22, 2005 #3
    so the size of macroscopic objects is much larger than what the uncertainty in their positions. i'm not sure what this means in regards to quantum mechanics. i find quantum physics so confusing and i highly respect anyone who understands and enjoys it.
     
  5. Mar 22, 2005 #4

    dextercioby

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    So QM has given u a number which is about 27 order of magnitude off the realms of macroscopical physics.The conclusion is simple:QM and the HUP in particular give nonsignificative results when applied to macroscopic objects.

    Daniel.
     
  6. Mar 22, 2005 #5
    this is probably a stupid question, but what exactly qualifies as macroscopic ie)what is the actual range?

    also, i get the question now. it was much simpler than what i was trying to make it out to be. thanks for the imput. you physics guys rock.
     
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