Banal(Electrostatics)

1. WHAT IS ELECTROSTATICS? Electrostatics is the branch of Physics, hich !eals ith static electric char"es or char"es at rest. #. WHAT IS $RICTIO%AL ELECTRICIT&? The electricity 'ro!(ce! by friction is calle! frictional electricity. If the char"es in a bo!y !o not )o*e, then, the frictional electricity is also +non as Static Electricity. 3. STATE THE APPLICATIONS OF PROPERTIES OF ATTRACTION &

REPLSIO% O$ CHAR-ES? The 'ro'erty of attraction an! re'(lsion b eteen char"e!  bo!ies ha*e )any a''lications s(ch as electrostatic 'aint s'rayin", 'o!er coatin", flyash collection in chi)neys, in+/et 'rintin" an! 'hotostat co'yin" 0ero23 etc. 4. WHAT ARE CO%5CTORS 6 I%SLATORS? -I7E EA8PLES 9o!ies hich allo the char"es to 'ass thro("h are calle! con!(ctors. e.". )etals, h()an bo!y, Earth etc. 9o!ies hich !o not allo the char"es to 'ass thro("h are calle! ins(lators. e.". "lass, )ica, ebonite, 'lastic :(antisation of electric char"e; The f(n!a)ental (nit of electric char"e 0e3 is the cha r"e carrie! by the electron an! its (nit is co(lo)b. e has the )a"nit(!e 1.< = 1>1 C. In nat(re, the electric char"e of any syste) is alays an inte"ral )(lti'le of the least a)o(nt of char"e. It )eans that the @(antity can ta+e only one of the !iscrete set of *al(es. The char"e, @  ne here n is an inte"er. 5. WRITE NOTE ON QUANTISATION OF ELECTRIC CHARGE

.5E$I%E ELECTRIC $IEL5 I%TE%SIT& Electric fiel! at a 'oint is )eas(re! in ter)s of electric fiel! intensity. Electric fiel! intensity at a 'oint, in an electric fiel! is !efine! as the force e2'erience! by a (nit 'ositi*e char"e +e't at that 'oint. It is a *ector @(antity. E $J@. The (nit of electric fiel! intensity is % C1. 11.5E$I%E ELECTRIC LI%ES O$ $ORCE. The conce't of fiel! lines as intro!(ce!  by 8ichael $ara!ay as an ai! in *is(aliKin" electric an! )a"netic fiel!s. Electric line of

force is an i)a"inary strai"ht or c(r*e! 'ath alon" hich a (nit 'ositi*e char"e ten!s to )o*e in an electric fiel!. 1#. STATE THE PROPERTIES O$ ELECTRIC LI%ES O$ $ORCE. 0i3 Lines of force start fro) 'ositi*e char"e an! ter)inate at ne"ati*e char"e. 0ii3 Lines of force ne* er intersect. 0iii3 The tan"ent to a line of force at any 'oint "i*es the !irection of the electric fiel! 0E3 at that 'oint. 0i*3 The n()ber of lines 'er (nit area, thro("h a 'lane at ri"ht an"les to the lines, is 'ro'ortional to the )a"nit(!e of E. This )eans that, here the lines of force are close to"ether, E is lar"e an! here they are far a'art, E is s)all. 0*3 Each (nit 'ositi*e char"e "i*es rise to 1 o lines of force in free s'ace. Hence n()ber of lines of force ori"inatin" fro) a 'oint char"e @ is % @  in free s'ace. 13. DEFINE ELECTRIC DIPOLE.GIVE EXAMPLES.

To e@(al an! o''osite char"es se'arate! by a *ery s)all !istance constit(te an electric !i'ole. Water, a))onia, carbon!io2i!e an! chlorofor) )olec(les are so)e e2a)'les of  'er)anent electric !i'oles 14.5E$I%E 5IPOLE 8O8E%T.WRITE EPRESSIO%,%IT. The )a"nit(!e of the !i'ole )o)ent is "i*en by the 'ro!(ct of the )a"nit(!e of the one of the char"es an! the !istance beteen the). Electric !i'ole )o)ent, '  @#! or #@!. It is a *ector @(antity an! acts fro) M@ to @. The (nit of !i'ole )o)ent is C ). 1.5E$I%E TOR:E EPERIE%CE5 9& ELECTRIC 5IPOLE? The )a"nit(!e of tor@(e is, N  One of the forces 2 'er'en!ic(lar !istance beteen the forces  $ 2 #! sin   @E 2 #! sin   'E sin  0@ = #!  P3 %ote ; If the !i'ole is 'lace! in a non(nifor) electric fiel! at an an"le , in a!!ition to a tor@(e, it also e2'eriences a force. 16. DEFINE ELECTRIC POTENTIAL ENERGY OF AN ELECTRIC DIPOLE

Electric 'otential ener"y of an electric !i'ole in an electrostatic fiel! is the or+ !one in rotatin" the !i'ole to the !esire! 'osition in the fiel!. 1F.5ESCRI9E THE WORI%- O$ 8ICROWA7E O7E%. It is (se! to coo+ the foo! in a short ti)e. When the o*en is o'erate!, the )icroa*es are "enerate!, hich in t(rn  'ro!(ce a non (nifor) oscillatin" electric fiel!. The ater )olec(les in the foo! hich are the electric !i'oles are e2cite! by an oscillatin" tor@(e. Hence fe bon!s in the ater )olec(les are bro+en, an! heat ener"y is 'ro!(ce!. This is (se! to coo+ foo!. The 'otential !ifference beteen to 'oints in an electric fiel! is !efine! as the a)o(nt of or+ !one in )o*in" a (nit 'ositi*e char"e fro) one 'oint to the other a"ainst the electric force. The (nit of 'otential !ifference is *olt 18. DEFINE POTENTIAL DIFFERENCE.

The 'otential !ifference beteen to 'oints is 1 *olt if 1 /o(le of or+ is !one in )o*in" 1 Co(lo)b of char"e fro) one 'oint to another a"ainst the electric force. 1!. DEFINE THE UNIT OF POTENTIAL DIFFERENCE. "#. DEFINE ELECTRIC POTENTIAL.

The electric 'otential in an electric fiel! at a 'oint is !efine! as the a)o(nt of or+ !one in )o*in" a (nit 'ositi*e char"e fro) infinity to that 'oint a"ainst the electric forces. #1.5E$I%E ELECTRIC POTE%TIAL E%ER-&. The electric 'otential ener"y of to  'oint char"es is e@(al to the or+ !one to asse)ble the char"es or or+!one in brin"in" each char"e or or+ !one in brin"in" a char"e fro) infinite !istance

##. 5E$I%E E:IPOTE%TIAL SR$ACE, If all the 'oints of a s(rface are at the sa)e electric 'otential,then the s(rface is calle! an e@(i'otential s(rface .If the char"e is to be )o*e! beteen any to 'oints on an e@(i'otential s(rface thro("h any 'ath, the or+ !one is Kero. #B.5E$I%E ELECTRIC $L The electric fl(2 is !efine! as the total n()ber of electric lines of force, crossin" thro("h the "i*en area.   E . !s #4.5E$I%E -ASSGS LAW -a(ssGs la states that the total fl(2 of the electric fiel! E o*er any close! s(rface is e@(al to1Jo ti)es the net char"e enclose! by the s(rface.  @Jo #.5E$I%E ELECTROSTATIC SHEIL5I%- Electrostatic sheil!in" is the 'rocess of isolatin" a certain re"ion of s'ace fro) e2ternal fiel!. It is base! on the fact that electric fiel! insi!e a con!(ctor is Kero. #