1. Light can affects the movement of electric charges,example, photoconductivity¹,photoresistivity², photovoltaic³effect,and photoelectochemical⁴ effect.
Note :
1. Photoconductivity – is an electrical phenomenon which,a material becomes more electrically conductive due to the absorption of electromagnetic radiation such as visible light, infrared light, or gamma radiation
2. Photoresistivity – a resistor whose resistance decreases with increasing incident light intensity. A photoresistor is made of a high resistance semiconductor. If light falling on the device and it is high enough frequency, and photons absorbed by the semiconductor give an electrons enough energy to jump into the conduction band,thereby lowering resistance.
3. Photovoltaic - is the creation of voltage or a electric current in a material, upon its exposure to light. Though the photovoltaic effect is directly related to the photoelectric effect, they are different processes. In the photoelectric effect, electrons are ejected from a material's surface upon its exposure to EMR. The photovoltaic effect is different as the electrons are transferred between different bands ( example,from valence band to conduction band ) within the material, resulting in the build up of voltage between two electrodes
4. Photoelectrochemical cells – also known as PEC solar cells generate electrical energy from light, including visible light.
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