For photoelectric effect to take place, the metal used as the cathode should have ________

High melting point
Low melting point
Low work function
Low resistance
Low work function  The photoelectric effect is the propensity of high energy electromagnetic radiation to eject electrons from a given material. The photoelectric effect has been utilized in devices called photocells, consisting of two electrodes in a sealed vacuum tube. By coating one electrode (the photocathode) with a alkali metal of low work function, a photo current could be generated even from visible light. Work function is the minimum energy needed to remove an electron from the surface of a material.

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