1. The problem statement, all variables and given/known data hey, 2 questions thanks: 1.A gamma ray is converted to an electron and a positron. If 50% of the gamma ray energy becomes kinetic energy, what is the wavelength of the gamma ray? 2.A nucleus of a radioactive element (mass 10^-25) loses 10^-26g during gamma decay. if the gamma ray has a wavelength of 10^-14m, what is the recoil velocity of the nucleus? 2. Relevant equations no idea, we havent learnt about wavelength at all.. however these two questions were in a big revision booklet so id rather be safe than sorry. 3. The attempt at a solution thanks.