0
votes
1answer
83 views

What does (simple) $j/cm^2$ represent AND how does this result $6.959j/cm^2$? [closed]

According to the image shown below, this specific Laser Hair Treatment device claims that it has a concentration of $6.959 j/cm^2$. So far by research I have found that it needs around $6\mbox{ to }7 ...
2
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1answer
356 views

Generated wavelength of free electron laser

Could you please help me understand how one can measure output frequency of free electron laser (provided that we know size of magnetic domains and electron energy)? This should be a function of ...