Answer: Photoelectric is characterized by or involving the emission of electrons from a surface by the action of light.
Photoelectric effect is the emission of electrons when a radiation of frequency higher than the threshold frequency falls on the surface of an element. The substance which undergoes photoelectric effect is called as photoelectric.
Ground state is the state representing the lowest energy state.
Excited state is the state which represents a high energy state.
An electron in ground state absorbs energy to move to the excited state.