A dimensional analysis problem.

AI Thread Summary
The discussion revolves around a dimensional analysis problem involving a constant with units of 1/mass and a function with units eV/A^2 that needs to be converted to THz^2. The approach suggested includes expressing mass in MeV/c^2 and converting c^2 into A^2/s^2. The calculations confirm that the reciprocal of mass in these units results in c^2/eV, leading to a simplification that yields Hz^2. The participants agree that Angstroms (A) is the correct unit for length in this context. Overall, the analysis appears sound and ready for further application.
lylos
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Homework Statement


Basically, I have a constant that is 1/mass. I need to find out how to relate this to my function which has units eV/A^2 to have results in THz^2.

Homework Equations


The Attempt at a Solution


I think I would just have the mass in units of MeV/c^2 and then convert c^2 into A^2/s^2... Does this sound correct?
 
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I think that will work, since A seems to be a length unit (Angstroms?) from what you say.

Let's see ... reciprocal of mass in your units would be c^2/eV, so:

<br /> \frac{c^2}{eV} \cdot \frac{eV}{A^2}<br /> = \frac{A^2}{s^2 \cdot eV} \cdot \frac{eV}{A^2}<br /> = \frac{1}{s^2}<br /> = Hz^2<br />
 
Redbelly98 said:
I think that will work, since A seems to be a length unit (Angstroms?) from what you say.

Let's see ... reciprocal of mass in your units would be c^2/eV, so:

<br /> \frac{c^2}{eV} \cdot \frac{eV}{A^2}<br /> = \frac{A^2}{s^2 \cdot eV} \cdot \frac{eV}{A^2}<br /> = \frac{1}{s^2}<br /> = Hz^2<br />

Yeah, it was Angstroms. That's what I was thinking it would be, was just wanting to run it through with someone else before I started over again. Thanks. :)
 
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