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### h-bar

Posted: Tue Apr 17, 2018 7:49 pm
In the Heisenberg uncertainty equation, does h-bar basically mean plancks constant divided by 2pi? Will this number always be the same/constant or are there instances where its different?

### Re: h-bar  [ENDORSED]

Posted: Wed Apr 18, 2018 2:03 pm
h bar is always $\frac{h}{2\pi }$

### Re: h-bar

Posted: Wed Apr 18, 2018 2:10 pm
Will we need to memorize the value of h-bar on the test next week?

### Re: h-bar

Posted: Fri Apr 20, 2018 2:31 pm
Since on Test #1 we are given many formulas we did not need for that test specifically, I think we can assume h bar will not be specifically given. The formula sheet does include the value of Planck's constant and pi so you can easily use that information and your knowledge of h bar to find the value needed.

### Re: h-bar

Posted: Fri Apr 20, 2018 7:53 pm
If h-bar is h/ 2*pi, where does the h/ 4*pi come from in the Heisenberg Indeterminancy Function come from?

### Re: h-bar

Posted: Sat Apr 21, 2018 12:13 pm
I was also confused between the practicality of using $\frac{h}{4\pi }$ instead of $\frac{h}{2\pi }$ . What is the difference between the two?

### Re: h-bar

Posted: Mon Apr 23, 2018 3:15 pm
h-bar is used because it is a common value for use with the Schroedinger equation. $\frac{h}{4\pi }$ is a derived quantity in the Heisenberg equation, but it is not represented with a special character because it does not show up as commonly in quantum mechanical equations compared to h-bar.

### Re: h-bar

Posted: Sun Apr 29, 2018 1:59 pm
The Uncertainty Equation stated in the textbook has 1/2 * h-bar, and since h-bar is h/2pi, we use h/4pi.