## 1B. 25 Uncertainty in Position

$\Delta p \Delta x\geq \frac{h}{4\pi }$

Isaac Wen
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### 1B. 25 Uncertainty in Position

Hi! Here's the question:
What is the minimum uncertainty in the speed of an electron confined within a lead atom of diameter 350. pm? Model the atom as a one-dimensional box with a length equal to the diameter of the actual atom.

I was just wondering why 350.pm is the uncertainty in the position. I understand that the units match up, but how is the length of a diameter related to the position of an electron?

HannahRobinson3L
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Joined: Wed Sep 30, 2020 9:51 pm
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### Re: 1B. 25 Uncertainty in Position

The 350. pm is the uncertainty of the position of the electron because the electron is somewhere within the confines of the atom. We don't know exactly where the electron is within the boundaries of the atom, but we know that it is in there somewhere, which is why the value of the diameter is used for the uncertainty of the position in this problem. Hope that makes sense.