1. The problem statement, all variables and given/known data What is the wavelength of an electron with a kinetic energy of 2.00 MeV? What is the wavelength of an electron with a kinetic energy of 2.08 GeV? (Possibly useful constants: hc = 1239.8 eVnm, rest energy of the electron: E0,e = 511.0 keV.) 2. Relevant equations [itex]\lambda[/itex]=hc/(2(mc2)K)1/2 3. The attempt at a solution Should be pretty straightforward, I keep getting the wrong answer though, should just be plug and chug, i would think.