Sunlight reaches us by radiation. Radiation travels in electromagnetic waves consisting of ______, and when the energy waves reach an object, they can either pass through it, or be reflected, or be absorbed, depending on the material. PVs are made out of a semi-conducting material. When they absorb photons of sunlight, the energy of the photons dislodges electrons from their atoms. The PV’s special coating attracts free electrons to the surface, and it is this movement of electrons that produces the electrical current.
A．electrons
B．photons
C．neutrons
D．atoms