Relation between kinetic energy and total energy in special relativity is...
E = K + mc2
Relationship between mass, energy and momentum is...
E2 = P2C2 + (mc2)2
A Fe nucleus at rest emits a 14.0-keV photon. Use conservation of energy and momentum to deduce the kinetic energy of the recoiling nucleus in electron volts. (Use Mc2 = 8.60E-9 J for the final state of the Fe nucleus.)
what I have so far is...
E = pc because E >> photon rest energy , which =...