how does the sensitive light works?

Question

SENSITIVE LIGHT

Answer 1

did you mean how does a light sensor work?

Answer 2

When dealing with light, always ask yourself what the tiny mass-less packets of energy traveling at the speed of light called photons are doing? The most energetic photons have the shortest wavelengths. Ultraviolet light (short wavelengths) is more energetic and penetrating than infrared light (long wavelengths). Ultraviolet sunlight can give you a sunburn while the infrared light merely warms you. Infrared light is used in heat lamps and ultraviolet light is used to kill bacteria. If photons are energetic enough they can knock electrons out of their orbits around atoms and molecules causing ionization (the photo-electric effect). The freed electrons can result in a flow of electricity if exposed to a voltage (using a battery?) and that flow can be detected and measured in a light sensor.