Heisenberg Uncertainty Principle homework Question

AI Thread Summary
The discussion revolves around a homework problem applying the Heisenberg Uncertainty Principle to a scenario where a woman drops rocks from a ladder. The goal is to demonstrate that the average miss distance is given by a specific equation involving Planck's constant, mass, height, and gravity. The participant has attempted substitutions but struggles to derive the required equation and seeks hints for clarification. Additionally, they express uncertainty about justifying their assumptions related to initial and final uncertainties. The thread highlights the complexities of applying quantum mechanics principles to classical physics problems.
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Sorry about not using symbols but I haven't learned how to do that yet.

1. Homework Statement

A woman is on a ladder of height H. She drops small rocks of mass m toward a point target on the floor.

Show that according to the Heisenberg Uncertainty Principle, the average miss distance must be at least

delta(x final) = sqrt [h/pi*m] * sqrt sqrt [2H/g]

where h is the Planck's constant,
pi is 3.14
m is the mass of the rock
H is the height from which the rock is dropped
g is the acceleration due to gravity.

Assume that delta(xfinal ) = delta(x initial) + (delta(v))*t
Also justify the assumption.

2. Homework Equations

delta(x) * delta(p) < or = [h/4*pi]

delta(p) = m * delta(v)

v= u +at
s= 0.5(u + v)t
s= ut +0.5at^2
v^2= u^2 +2as

3. The Attempt at a Solution

I did a couple of substitutions and got something like t=sqrt[2H/g] and delta(v)=sqrt[2gH] but I can't seem to get the equation needed. Tried for 2 hours and can't seem to understand it all. Please help? Or at least give some hints. Also, I don't know how to justify the assumption above.
 
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Nvm. I found a similar answer in another thread.
 
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