Electric charge from light -photovoltaic effect:-

A cell is a metallic “sandwich or disk ”compose is three layers of materials. one outside layer is made of iron .another side layer is made of semitransparent materials which permit light to pass through. the center layer materials are composed of selenium alloy. the two outsides layers work as two electrodes. 

When light is focused on the selenium alloy through transparent materials an electric charge is developed between two outside layers. if the material is attached across these layers the amount of charge can be measured. direct use of this type of cell is the common light meter as used for photography determining the amount of light that is present.

Electric charge from light-photoelectric cell or phototube:- 

photoelectric cell or phototube commonly called “electric eye” or “PE Cell” operate the principle of the photocell the photoelectric cell,  however, depend open a battery or some other source of electrical pressure in its operation of detecting changes in light.  

The photocell has many uses, some of which are automatic handling dimmers on automobiles, motion picture machines, automatic door openers, and drinking fountains. 

Electricity from chemical action:-

So, far you have discovered what electricity is and several sources of energy which may be used to produce it. another source of electricity commonly used is the chemical action houses in electric cells and batteries. 

Batteries are usually used for emergencies and portable electric power. whenever you used a flashlight emergency learned or portable equipment, you will be using batteries.  batteries are the main source of the power of the present ay of the submarine.in addition, there is a wide variety of equipment, which used cell or batteries either as normal or emergency power. “Dead” batteries are a common type of equipment failure and such failure are can be very serious.

Cells and batteries required more care and maintenance than most of the equipment in which you will work. even though you may be using only a few cells and batteries, if you find out how they work, where they were used, and how to properly care for them, you will save time and in many cases a lot of hard work.

Now you will find out how chemical action produces electricity and the proper use and care of the cell and batteries that houses chemical action. photoelectric cell and electrons movement occurs as light strikes the light-sensitive materials.