Answer:
when a photon is created by an electron in a higher energy level. The electron looses energy and move to a lower energy level.
Explanation:
energy levels refer to various levels of energy possessed by the electrons in an atom. An electron in a higher energy level possesses more energy and more speed that that in a lower energy level. Electrons can move from one energy level to another when they gain energy from the surroundings or loose energy to the surroundings. They leave their energy level to fit into a new level where the energy level is same with the energy they now possess. Electrons hit by a photon tend to move to higher energy levels. But if an electron creates a photon it drops to a lower energy level
