1. The problem statement, all variables and given/known data Electrons are accelerated through a potential V and then they are suddenly stopped and emit photons. Derive the minimal value that the potential should have in order to produce some X-Ray photons of wavelength 10-10m. 2. Relevant equations E=hc/λ V=(h/e)(f-f0) 3. The attempt at a solution I used E=hc/λ to find the energy of the X ray photons. I found E= 1.989x10-15 = 12431.25 eV Not sure if I needed to do this or what to do next. All help is appreciated. Thank you.