## post Module Heisenberg

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

ElizabethP1L
Posts: 59
Joined: Wed Nov 15, 2017 3:01 am

### post Module Heisenberg

Hey, everyone! I'm not really sure how to do the following problem. I keep getting he wrong answer regardless of how many times I attempt to calculate it:

The hydrogen atom has a radius of approximately 0.05 nm. Assume that we know the position of an electron to an accuracy of 1 % of the hydrogen radius, calculate the uncertainty in the speed of the electron using the Heisenberg uncertainty principle.

The answer is D. Delta v >= 108 m/s, Delta v is very high. In knowing with certainty the position of the electron to within 1 % of the hydrogen atom radius the resulting uncertainty in the electron's speed is so high that we essentially do not know its speed at the same time that we know its position.

Any help on this problem would be greatly appreciated. Thanks!

Chem_Mod
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Joined: Thu Aug 04, 2011 1:53 pm
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### Re: post Module Heisenberg

First you have to determine the uncertainty in position which is given as 1% of 0.05nm. Use the heisenberg equation on the constants and equations sheet to find your uncertainty in velocity. Some points to keep in mind are that
1. Heisenberg's equation uses h (planck's constant) which has the units Joules. Therefore, all other units should be in kg, meters, seconds, and/or Joules. For example, the radius is given in nm and must be converted into meters.
2. The Delta symbols in the equations signfiy "uncertainty" not "change in". Therefore, DeltaV means uncertainty in velocity.