What happens when an electron emits a photon?

an electron emits a photon and falls from a higher energy level to a lower energy level.
an electron emits a photon and jumps from a lower energy level to a higher energy level.
an electron emits a photon and jumps from a middle energy level to the valence shell.
an electron emits a photon and stays at a higher energy level.

Will give brainliest! which statement best describes the difference between strong nuclear forces and weak nuclear forces? weak nuclear forces are involved when certain types of atoms break down. strong nuclear forces are responsible for holding atoms' nucleus together. weak nuclear forces hold bonds between atoms together. strong nuclear forces hold together the nucleus of an atom. strong nuclear bonds prevent atoms from falling apart. weak nuclear bonds prevent compounds from falling apart. strong nuclear forces are involved in breaking electrons from their shells. weak nuclear forces hold protons in the nucleus.

If the ama of the inclined plane below is 2, calculate the ima and efficiency. ima = efficiency =

If two students are running down the hall toward each other, trying to get to class, and they have the same mass and acceleration, what will happen when they collide? will their forces cancel out or will each one experience a reaction?