Project on Resistor

 

Proj Projec ectt Work  On Physics Subject: Resistors

 NAME: asasasasasas asasasasasas CLASS: XII A ROLL NO: 0 RE!IS"RA" RE!IS"RA"ION ION NO:

CERTIFICATE

"his

is

to

certi#y

that

this

$roject

%RESIS"ORS& has been co'$(ete) by Anisha Pau( the stu)ent o# Sssssssssssss Schoo(* Ro+riah* ,orhat.

Subject teacher: Riju'oni Payen-

E.terna(/s si-nature:

ACKNOWLEDGMENT I Anisha Pau( hereby ackno+(e)-e that a(( the )etai(s #urnishe) in this $roject are true to the  best o# 'y kno+(e)-e "his $roject entit(e) %RESIS"ORS& sub'itte) #or the aca)e'ic year  102324 is a recor) +ork )one by 'e un)er the -ui)ance o# our bio(o-y teacher 'aa' Riju'oni Payen- I ha5e $ut in best o# 'y e##orts to 'ake this $roject success#u( "his is a bona #i)e recor) o# the ori-ina( +ork )one by 'e I ackno+(e)-e +ith -ratitu)e the kin) he($ an) encoura-e'ent recei5e) #ro' our bio(o-y teacher )urin- the $re$aration o# the $roject My sincere thanks are )ue to the Princi$a( 'aa' Rinku 6or-ohain* Sssssssssssss Schoo(* #or her  constant su$$ort At the en) I +oun) (ike to thank 'y $arents an) #rien)s #or he($ an) a$$reciation +ithout +hich is +ou() not ha5e  been $ossib(e #or us to co'$(ete the assi-n'ent

Bibliography i7 Pra)ee$s re#erence book  ii7 +++yahooco' iii7 ++++iki$e)iaco' i57 NCER" "EX" 6OO8 

INDEX I Intro)uction II Oh'/s La+ III 9e$en)ence I Li'itation o# oh'/s (a+  Resisti5ity o# 5arious 'ateria(s I Co'binations II 8ircho##/s (a+

 

IN"RO9;C"ION

A resistor is a $assi5e t+o3ter'ina( e(ectrica( co'$onent that i'$(e'ents e(ectrica( resistance as a circuit e(e'ent Resistors act to re)uce current #(o+ an) at the sa'e ti'e act to (o+er 5o(ta-e (e5e(s +ithin circuits In e(ectronic circuits resistors are use) to (i'it current #(o+ to a)just si-na( (e5e(s bias acti5e e(e'ents an) to ter'inate trans'ission (ines a'on- other uses uitous in e(ectrica( e>ui$'ent Its resistance s$eci#ies the e(ectrica( #unction o# a resistor

Oui5a(ent to 5o(t $er a'$ere Since resistors are s$eci#ie) an) 'anu#acture) DDDDDDDDDDDDDDDDDDDDDDDDDDDDDD

 

9EPEN9ENCE

a7 Resistance on (en-th o# con)uctor: Consi)er a con)uctor satis#yin- BRI to be in the #or' o# s(ab o# (en-th ?(7 an) cross sectiona( area ?A7 Resistance o# s(abB VI=R   No+ $(ace to i)entica( s(abs so that the (en-th beco'es 1( an) current #(o+in- throu-ht the either s(ab is ( the  $otentia( )i##erence across the en)s o# #irst s(ab is  then #or the secon) s(ab a(so is  Potentia( )i##erence across the co'bination is e>ua( to the $otentia( )i##erences across in)i5i)ua( s(abs BB1 "he current throu-h the co'bination is (* so the resistance o# the co'bination is* RB1IB1R  "hus )oub(in- the (en-th o# the con)uctor kee$in- area cross section A constant )oub(es the resistance Resistance is )irect(y $ro$ortiona( to Len-th  b7 Resistance u$on cross sectiona( area A o# a con)uctor   No+ i'a-ine )i5i)in- the s(ab into t+o i)entica( s(abs o# (en-th ( an) area A1 Current throu-h each s(absB (1 Potentia( )i##erence across each ha(# s(absB Resistance o# each ha(# s(ab RB I1B1IB1R  "hus +hen cross section area is ha(5e)* resistance is )oub(e) "here#ore* resistance is in5erse(y $ro$ortiona( to area o# cross3section RBrho (A "he constant o# $ro$ortiona(ity ?rho7 )e$en)s on the 'ateria( o# the con)uctor but not on it )i'ension Rho is kno+n resisti5ity or s$eci#ic resistance

Rho= R.Al Resisti5ity is one ty$e o# resistance +here rho an) (en-th are unity ie rhoBR  Its unit is* rhoBoh''?17 ' 9i'ension o# resisti5ity: rhoBF ML?3@7"?3@7A?317G

LIMI"A"IONS O= O
Resisti5ity o# arious Materia(s

Meta(s ha5e resisti5ity in the ran-e o# 20?3H7 oh' ' to 20?347 oh' ' Insu(ators ha5e resisti5ities 20?2H7 ti'es -reater than 'eta( or 'ore Se'icon)uctors ha5e resisti5ities in bet+een con)uctor an) insu(tors Resisti5ity o# se'icon)uctors )ecreases +ith a rise in te'$erature "heir resisti5ity is a##ecte) by the  $resence o# s'a(( a'ount o# i'$urities Co''ercia((y $ro)uce) resistors #or )o'estic as +e(( s (aboratory use are o# t+o ty$es: i7 Wire boun) resistors ii7 Carbon resistors Wire boun) resistors are 'a)e by +in)in- +ires o# a((oys ie 'a-nanin* constantan* etc "hese +ires are chosen because their resisti5ities are re(ati5e(y insensiti5e to te'$erature Resistors o# ran-e hi-her than +ire boun) are 'ost(y 'a)e o# carbon Carbon resistors are s'a((* co'$act an) (ess e.$ensi5e so are +i)e(y use in e(ectronic )e5ices