question: What is the photoelectric effect ?
answer: the emission of electrons ( called `` photoelectrons '' ) from a surface when light is shone on it
turker_answer: The photoelectric effect is the emission of electrons ( called `` photoelectrons '' ) from a surface when light is shone on it .
rule-based: The photoelectric effect is the emission of electrons ( called `` photoelectrons '' ) from a surface when light is shone on it .