An electron with a speed of 1.4 ×106m/s collides with an atom of element x. shortly afterward, the atom emits a 1240 nm photon. what was the electron's speed after the collision? assume that, because the atom is so much more massive than the electron, the recoil of the atom is negligible. hint: the energy of the photon is not the energy transferred to the atom in the collision.

Two manned satellites approaching one another at a relative speed of 0.550 m/s intend to dock. the first has a mass of 2.50 ✕ 103 kg, and the second a mass of 7.50 ✕ 103 kg. assume that the positive direction is directed from the second satellite towards the first satellite. (a) calculate the final velocity after docking, in the frame of reference in which the first satellite was originally at rest.(b) what is the loss of kinetic energy in this inelastic collision? (c) repeat both parts, in the frame of reference in which the second satellite was originally at rest. final velocity(d) loss of kinetic energy = ?