Question: A newly discovered particle, the SPARTYON, has a mass 455 times that of an electron. If a SPARTYON at rest absorbs an anti-SPARTYON, the mass of an electron is 9.11×10-31 kg.
A- What is the frequency of each of the emitted photons (in 1020 Hz)?
I known the correct answer but I need to know how to get that. Thanks in advance!