(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

h/(mc) = ?

where m is the mass of an electron

2. Relevant equations

3. The attempt at a solution

h = 4.136*10^-15 eV*s

m = 0.511 MeV/c^2

c = 299792458 m/s

So m*c (as long as I remember to multiply by 10^6) gives units of eV/c

So h/(mc) gives units of s*c

Using the values I've written here, I would get

h/(mc) = 2.6998*10^-29 s*c

But c has units of m/s, so I can get units of m by multiplying by the numerical value of c, right? Then I multiply by 10^9 to get units of nm, and I get

h/(mc) = 8.09*10^-12 nm

But this is wrong, because the answer is 0.002426 nm.

I can't believe I can't do a simple plug-in problem, but, well, it should be easy enough to help me with.

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# Finding the Compton wavelength of the electron

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