# Homework Help: Theory question

1. Mar 21, 2005

### jaidon

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. Mar 21, 2005

### dextercioby

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

Daniel.

3. Mar 22, 2005

### jaidon

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.

4. Mar 22, 2005

### dextercioby

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.

5. Mar 22, 2005

### jaidon

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.