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· 5. Elec+irici+y ond m0-~ ne+i6m
5i Electric ~-1dJs
E le.crnc cha~.
-s'1rnbo\ ,_ Q unit: C (courom 'b)
1)-r,0~1nve. i ne.S\a.twe. (\i<.es tt~e..\ Jo,?O~'\e..'.:> o.t\ro.c+')
. (pro\ons") (ele.i \wns")
1) ·, s co.nse.rved. =1 co.N'to- l:,e c..re.o,.,kc,l or Je.~®'-fed..
3)1'> ':i')Of\i1,eol --::'yame'> ,n J;scte--\e "'d.a.•~t''' e =e\emeomr'( cn1e
e..ledmn = -e Dmton = +e
-= -1Gxl0 1 ~C.. (coulot'l\b) 1 = t1 Cox10Jc.. Ex.
1oto.l c\rio.1{- = +~e.- 2e -.le.."' 3.l x
1 ~C. Cou\ornb'~ Lo..w
· s-z.e o~ +he. electric
c00\ombl ( ~S. '3~J1IO") cof'l':i'°-1"1 l ~,ie o~ cho.ries ,--------t----=.:....../--, F== K I 2 rl J;::,tcmce be-we.en ~ 1 ' a"J ':\t r= 1rn ( f= -z -1".) -
f-::: '3:Y:lxlOeix. 1Gl(IO x}\b,clO -::. 5xlO,.gtJ
Ex
I .,- .- ---- viF=J__ ~,5-1-, : i,1Tf 0 (1. I l....---- ___ _j F-=- ~)( i.i5xl 1 iJ
E\e.c-\nc tie.\J eledric. per,ni#iviJy
& wcuum
( iasx l6'i) F,e\J. = ever,/ f01f1l ,n 5face has o... 'IJu.m~e.r (or ve.<e'kl r) E. d. ''1 r r'll-pero:tuve.. ,\ d J 11
,I( (^31) .1(}1,1 , f (^) i., X. '
~a. \o.r e\c;l e\e.cJric. ~e\J. 5'rte,~th r ' " E =£
ne -.
t F I^ l:..
Q ) •J' I =^ kQ3;
ri. =kQ
., °^
r1. 1 - I'
oQ. ~lec,tr\ci±-y_ ~o E-t1eld (^) wi+h E-Ael&
<. E
0 0-0li )
5
m/~
' I '
- f 6)-neJ&rn - roovemmt t ele:b trnn~ are sl<'--ult
Jn-tnn
,~·1~:>t u the ~elJ l)Jiliftrtveloc,~y Vn rnrrf:>
EK
= c.orrtn't ;amoont ot charae Fine; o. paint- eac.h seconc:L 1t.---+--C.l't)SS Secoonct \ tl'"'-'4. I=1A -i>
c~~e. per c.~e co.rrie.r
~rit+ speed ·. I=- ~Q / le.t Dt·=h bt'
I=AQ (inside c-,1.)
- ~hwae cnrt. V x ChQ~C'. V ch.atrrie~
:tt: e}ectrons = 101.~ 1Y(^1
vol. o{ri-P+ '5-peect?
1.-=nAvq
2'6 T l -l'J -5 , · -, 1 -= 10 '-lT-"'(2x1o~)x.V x.1.GxlO -'1V~5x/D ms-=05~m
po-\enho:\ ~l~rence.: ele(.frica.l ,,....---._) li~nl, ( loo~pea.ker,I )
IC, at v\ ene1'/. hjoJ:,J mol-or) larnp.)--
p .) ) .. ,
e.\e.d'romotive torce.! e\ectrico.) l_ijYI~_, ~olar cel.s J )
ene.f??\ CH'em1cal, oo.1-1-eryJ (p (^) E ot elec..trons ut^ 5CXJndv· · ·.^ microphM1e^1 _ •.
En ~~-p~,~cl iyex- oC\·~ C..,Y)os<;ie. -
' e.ctronvo t u
e V= e,n~~ ~ained br an e.ledmn when it moves +hro°(jh
0 p.ol. o~ one. volt.
KE of +he e_\ectrori when it hirs the t lo-k?
----1i
KE:W= -I~^1 -I~^1
1
V::1.bxl0 C,x1V = (.xlOJ = e\edro/\u,
. V=1V
( 5.J ( *heMiCc.* \j 5.lHeo:hn~ eWect of on electric c_l)rrenl 5 • ½ mo..cf'e.t-41,
- D,re_c+ con-ent (tx.):c Cha.~ tlow in one. directio 'Alkrfla.-nf'\i conot (AO-= clirtdiOr\ of +he current cho.n~es ( ~ 100 tme.~ /s)
Re<::iistunc.e.. =- ?ole_riha.\ olil'e.rence. o..c (0')':> t~e ~()0\t
(ri ex cornvonenl') c..urre.nt ' 1 n the_ com-po(\ef\t
~. L___!_
Ohm'~ lo.w : the ,-polenful dif~reoc~ o.cross a_ me+oJ(ic
COf\Jud-or i"::i -pr~or\i. 'ooa\ to the... c0crent
'1n the. co~tllX.t--or if 1 its kmpero.tul'l- iS
Cofl :::itan t
Pol).)e r-
. Ene~ oleliverwl to Cl conclu.c+-or eac.11 Se.c.oncl! ~= \LI tr= f I \P=Rr1] voltu~e. ocrOSS the c_ondoctor
Comb, nin~ re6i~tor'.:l
V c.urrernin ea.ch^ s^ ome
I ,--------' COrnjX)Oellt .____, L..L,,,...... v, V2 Vl
Ex. To+al re.~.-,~ance. ·111 the.. c'ircuit'
volh
e Sarne / over ~Qlh c.ornpaneM ..;, P<;= 20 t IO: 30 _ .,/. 1 _ i+i-=~
y- 5 ID ID
Q,"' I0/ ( \ (^) ~ (^) 101., -.
+ C,.,es,
20 ; 1_j_+j_,.2, \2.. - 30 2.0 GO R~"g~11.. R_ =- 12 t 10 = 15 I/:, 15 ·
-~ ___,I 1s.3~-- -
~. /o-\me\er read\oi
V= 12.ia 1.
v10, = RTh,Im
\lV
I=V~.Y_
I<- 12,o t~io
= ;-Rio , '/,.v
Riot ~
"' l:.Q__ V ,.. 1 xl:l. : <ZV IOtW o - /,^. 11Vl
J_ : J._ t J_ RII B.1. ~
Rn ~ro 1000
11v-
\Jea\ k non-id~\ me¼?rs
- \ n order ~r the me~rs not --o 1r)ter~.ere..
resis4nnce h
in~ n; \e CiolroJ) Hi h
so no curren-1- 506 rol(j
i+ I fZ.eal!y ~ioHt
I
I I , ) I I I I ' I I I I / I (^) I I I I I I
. CntJodute 1.0.r. resis\tlr)
- IJJe. ose °' -po-kntal divickr to /Or~ the vo+rtie.
O\Jtr o... component.
E.rj. \JO\ume_ c..ontrol J Ii ~ht cl.immer
Problem ( co.n'+__ ~ e nhis c9r,f,)echon} ·. , 1
riv -
Hi" volto.3e: 1000 x llV %.I L~V
I
Hax volta3e: 1060 i<. 11v = 12v
1000f- ;' very . imikJ~ (,~'ti+ <:. 'oriu"'t or ver1 btft;
solu-hon
nv-
¼ink Ii ke this
I7 l
5. E lecnic. ce\:,
E"1+ orio- ,nren,a.l re sr;)ta.nce
j_ cell - E ::: em~ voltocf cJ- o._ source l.
wnen ·no corre(\ t ~\a.Jll
(adv~\~ ~"I \JU)f ,- - cell (^) I r f. 1 I
'··. - _'.
I r= 'in\erno.\ · re.r:.i~tancP. 1
= re.s,~tarice of the. eel\ ihe.J~
R. (increose..s as .it'~ ose.cl ") conMt mea::iure. / dire_c:rly E= Vp_-t'ilr
-= RI +rl
l_E T(IL•rl] OLro~"::> t'ne.:- re,si~-nr- == 1.~N. f.. = 1. 44V. r~? w; vo\l-o.~e. O\ICf \Ire. \oacl ~::.\JL+Yr 50Jl- v =1. 91 V 'I. 44 = t 41 .i. V r
Yr =0 .01\J
/ = r i - 7 r= y_ .., o.o,
"J::, ijj_ ~o. 02.ilA 50 I o oii2.
:di Jl.
{-,c__ t,i(i) @ r@Cs~lJ
fi,5JoJle
Power
en~roy ITUN,krreJ TQ g.: 1 \N= QV I .r=ri I
I=~ ='>'1n time lll J Q cY)arcf move~ thmu0~
tV" e.. c.o II du. C. -h:l I. -=') Q=I6t W=QV-=- Il)tV =") W =IV Dt El( R l P=IV - 1 )=RI~= ~ 2 ~J I E.
Total pcwe( :
' Co.pO:c"1ty !::. obili+-~ ot °' cell -\o l'ele~ cha~e.. (of- °' eel\ ) tK Sa.rn~n
$8 30C0rflA' \Pnon~ '/.... :)..1-00 MAh 3oOO rr1Ah =1 con su.pply 3000 (Y)A ~or 1h or 1rnA &r- 3'.:XOh or ')mA ~r 1500 h ( hve.. +o on ex ~f)t-)
Internal resistance graph - question
- 10 0.20 0.10 G.-10 0-'0 0.60 0. 70 0.M> 0..90 t O U U 1J [ \ ¥::,· ·itzo l1a.1.! + · • m, JI A t,. ;, •. «i ?:@ 1 l::i:+: ·~ .~ l:b '
@ E,_ ={.5V
@ I~ ti~
J,... 15
Ailernahve~ Choose a. f 0 .,M
t,~I(ll+rJ
£~:r12+Ir
·-1.S-= D.+i +0.6 r ==1 r==- .2~
The graph to the left depicts the voltage across the cell (or equally across the variable resistor) as the variable resistance is increased. Detemine: a) The emf of the cell b) The current in the external circuit when the variable resistor is reduced to zero c) The internal resistance of the cell
A ., corre(\t t?r:Golu.c.e.s , 1 o.
. ~-\ru.iGht wire..
]ErI = --: (^) I ;
BL~
1 1@~er R ,~ l t I • I I I
