1. The problem statement, all variables and given/known data At what Kinetic energy will a particle's debroglie wavelength equal its Compton Wavelength 2. Relevant equations DeBroglie λ = h/mv Compton λ = h/mc 3. The attempt at a solution Setting the two equations equal to eachother, I got v = c, then said KE = (1/2)mc^2, but somehow that just doesn't sound right. What do you think?