Xerography | Photocopier | How photocopy machine works

In this video details of Xerography or photocopier are given.
This video is excellent for FSc 2nd year physics students.
Xerography was invented by Chester Floyd Carlson.
Photocopy is done by a cylinder. Inner portion is made of Aluminium.Outer portion is made of Selenium.Selenium is a photoconductor.We sprinkle positive charge over Selenium.
Lamp is switched on. The image of document appears on the drum. The area where light falls selenium conducts charge disappears. In dark areas selenium acts as insulator. Charge remains on the drum. Toner is given negative charge and sprayed on the drum. It sticks with positive charge areas. Then drum is rolled over the white paper. Where ink stick with the paper.Paper is passed through heated rollers so that ink may get deep into the paper.

[@ahmadhayat8402]

Thanks alot sir,your video has removed all my confusions .........God bless you ...

[@warshanzafri2518]

Thanks yr. Your video helped me alot and got the idea of working of photocopier machine.

[@SherryTheMedico]

Great explanation. Thank you Sir

[@ahmadshah1136]

Thanks for such well explanation

[@muhammadsiddique8105]

Jizzak Allah

[@ARali36]

You have good information SIR

[@rameezwaniii]

Nice, keep at it sir.

[@muhammadsiddique8105]

Very good sir g

[@rajpurohit8441]

Love from india

[@crackanydifferentiation2904]

Thank you

[@HamidXen]

JazakUllah sir very briefly and easily explained

[@nimragul8583]

Thank you for your efforts

[@user-oq8lv5zd9o]

thank you so much Allah bless you

[@anasahmad3859]

Good carry on sir....aisy e sari book k topicwise lectures upload kar den

[@saqibalisaqibali1062]

Assalam o alaikum! Sir kya hal he? Sir wo na exercise questions ke saath numerical problem be kar dya kare.please

[@unsaali4201]

thank u so much sir lekn ek baat mujhey smj nahi ae k 5:30 pe letter E ka jo image hai vo positively charge dikhaya jaa raha hai phrr agr jab toner drum pe lagay ga jo k negatively charge hotaa hai to kya E ka image neutral hojaye ga? i mean jab barabar positive aur negative charges hotay hain phrr cheez neutral hojati hai aur ye puchna thaa k jis paper pe humein photocopy kerna hai yaani jo page heated roller se guzray ga uss per kon sa charge hogaa yaani ye toh apne bata diya k page heated roller se guzray ga uss per image mil jaye gee lekn uss paper pe image kese banay gee uss k paas kon sa charge hotaa hai aur vo kis charge ko attract karay ga ya kis ko repel karay ga

[@eliyajaffry369]

Thank you so much sir....Allah bless you .

[@masaudkhan1678]

boht ala zbr 10

[@HaiderJaffry01]

Thanks

[@zuhair2862]

How can we sprinkle positive charge on selenium?

[@ahmedshah3005]

Great sir ...

[@moazzamsultan1082]

God bless you

[@Arielprincesssss]

U nailed it

[@educationalandindustrialpr2252]

cool

[@masaudkhan1678]

very nice

[@awaisazmat9394]

Bohat acha thanks

[@maherzain9381]

Great

[@waqaskhanarmani9787]

Great sir

[@allinone2491]

ALLAH BLESS YOU SIR G

[@moazzamsultan1082]

Nice sir

[@scienceslashsab9455]

How can I thnxxxxxx to u sir

[@saeedashabbirshabbir4950]

Good way

[@guerrafatima3610]

why lght will not reflect back by black area..? although by these areas, lght should have to reflct bck..we can consdr it as. lght will collide with letters and then bounce back while at blank places lght will absorb.. .and if a paper is written by a mrker colr then the colourd words also bhve lke a dark region???

[@physicswisdom]

black absorb light completely other colours absorb partially and white absorb minimum light

[@shahistahussain3362]

Thanks sir

[@malihanif5191]

Nyc

[@physicswisdom]

Thanks

[@latifullahkhaksar9918]

Thanks sir g!

[@ahmadfarooq9623]

thank you sir..

[@saqibalisaqibali1062]

Or ap chapter13 ke theories kb upload kare ge?

[@moazzamsultan1082]

Good

[@theknowledge1151]

Nice

[@physicswisdom]

Thanks

[@moazzamsultan1082]

Be happy

[@kailashkmo7015]

Discover aur invent me fark hai sir

[@physicswisdom]

g

[@kailashkmo7015]

Aapko pata hai.. Aur aapne invent ko discover keh diya..😂

[@physicswisdom]

its called slip of tongue.

[@kailashkmo7015]

No problem.. good information.. bdw . It was helpful..

[@malihanif5191]

Sir g

[@theknowledge1151]

Sir ji please inkjet printer par video bana dain

[@physicswisdom]

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