An atom of mass M is initially at rest, in its ground state. Amoving (nonrelativistic) electron of mass me collides with theatom. The atom+electron system can exist in an excited state inwhich the electron is absorbed into the atom. The excited state hasan extra, "internal," energy E relative to the atom's ground state.(Figure 1) Part A Find the kinetic energy Ke that the electron musthave in order to excite the atom. Express your answer in terms ofE, me, and M.