$BJ*M}9V5A0lMw$X$b$I$k(J

2003$BG/EYHG(J

$BBh#12s!!@EEE5$(J

$B!ZFbMF![(J
$B!!(J
$BEE5$E*$JNO$OEE3&$H$$$&>l$r2p$7$FEA$o$k!#$D$^$jEE2Y$O<~$j$KEE3&$r:n$j!"$=$NEE3&$KCV$+$l$?JL$NEE2Y$ONO$r

$B!Z9`L\![(J

$B"!EE2Y(J
$B!!!!(J
$B@EEE5$$N85$O2?$@$m$&$+!)(J

$B"!%/!<%m%s$NK!B'(J
$B!!!!EE2YF1;N$N4V$G$O!"NO$O$I$N$h$&$KF/$/$N$@$m$&$+!)K|M-0zNO$H$N6&DLE@$HAj0cE@$O!)(J

$B"!EE3&(J
$B!!!!EE3&$H$O2?$@$m$&$+!)!!$^$?$=$NI=$7J}$O!)(J

$B"!EE0L(J
$B!!!!EE5$E*$JNO$K$h$k0LCV%(%M%k%.!<$O$I$N$h$&$K$J$k$@$m$&$+!)(J$B!!!!(J


$B!}$*A&$a$N;29M;qNA(J$B!JK\3X$N?^=q4[$K$"$j$^$9!K(J

$B!&!V@EEE5$!W!J=iEyJ*M}%7%j!<%:(J4)$B!!1JED0l@6Cx!!G]Iw4[(J
$B!!!!!!(J$B@EEE5$$N2J3X;K$b>\$7$/:\$C$F$$$^$9!#(J

$B!&!V@EEE5$$N(JABC : $BBSEE$NFf2r$-$+$iKI$.J}!"1~MQ$^$G!W(J $BDi0f(J $B?.NOCx!!9VCL
$B!!!!!!(J$B!JC;Bg?^=q4[$K$"$j$^$9!K(J

$B!N%S%G%*!O(J$B!&!&!&?^=q4[$G8+$k$3$H$,$G$-$^$9(J
$B!&@EEE5$$NIT;W5D!]AG@2$i$7$$%5%$%(%s%9$N@$3&(J8$B!]!J(J30$BJ,!K(J

$B!&EE>l$HEE5$NO!]%a%+%K%+%k%f%K%P!<%9(J17$B!]!J(J17$BJ,!K(J
$B!!!!!!!!!!!!!!!!(J$BJ]B8=q8K$K$"$j$^$9$N$G!"%+%&%s%?!<$GMj$s$G$/$@$5$$(J

$B!&EyEE0L$HEE>l!]%a%+%K%+%k%f%K%P!<%9(J19$B!]!J(J15$BJ,!K(J
$B!!!!!!!!!!!!!!!!(J$BJ]B8=q8K$K$"$j$^$9$N$G!"%+%&%s%?!<$GMj$s$G$/$@$5$$(J


$B!!(J

$B"!EE2Y(J(electric charge)

$B!!`h`a!J%3%O%/!K$r$3$9$k$H1)LS$J$I$r0z$-$D$1$k$h$&$K$J$k$3$H$O!"%.%j%7%c;~Be$+$iCN$i$l$F$$$?!##1#6@$5*$K$J$C$F!"%$%.%j%9$N%.%k%P!<%H(J(W.Gilbert)$B$O%3%O%/0J30$K$bB?$/$NJ*N$7$F(Jelectrica$B$HL>$E$1$?!#$3$l$+$i8=:_;H$o$l$F$$$k(Jelectricity$B!JEE5$!K$H$$$&8@MU$,@8$^$l$?$N$G$"$k!#(J
$B!!$5$F!"K|M-0zNO$N8;$,l9g$O0zNO$P$+$j$G$J$/@MNO$b$"$k$N$G!"EE2Y$O#2$l;f$G$3$9$C$F6a$E$1$k$HH?H/$9$k!#$D$^$jF1$8$E$1$?!#$3$l$,:#F|$G$b;H$o$l$F$$$k!#(J

$B!}EE2Y$rC4$&$b$N(J
$B!!(J1874$BG/$K%$%.%j%9$N%/%k%C%/%9(J(W.Crookes)$B$O??6uJ|EE$N:]!"1"6K$+$iIi$NEE5$$rBS$S$?N3;R$,=P$F$$$k$3$H$rH/8+$7$?!#$3$l$OEE05$r2C$($F$$$l$PN.$lB3$1$k$3$H$J$I$+$i!"J* $B!!86;R3K$NEE2Y$H$=$N<~$j$NEE;R$NEE2Y$NBg$-$5$OF1$8$J$N$G!"BG$A>C$79g$C$F86;RA4BN$H$7$F$OEE2Y$r;}$?$J$$!#$U$D$&!"J*J,$JEE;R$,Mh$k$?$a$KIi$KBSEE$7!";f$OEE;R$,ITB-$9$k$N$G@5$KBSEE$9$k$3$H$K$J$k!#J*

$B!{EE2Y$NC10L(J
$B!!#1(JA$B$NEEN.$,#1IC4V$K1?$VEE2Y$r#1#C!J%/!<%m%s!K$H$$$&!#EE;R$NEE2Y$O(J-1.6$B!_(J10-19 C$B$G$"$k!#(J

$B%H%C%W(J$B!!!!!!(J


$B"!%/!<%m%s$NK!B'(J
$B!!(J1785$BG/$K%U%i%s%9$N%/!<%m%s(J(C.A.de Coulomb)$B$O!"@:L)$J$M$8$jGi$r$D$/$C$FEE2Y$N4V$KF/$/NO$rB,Dj$7$?!#$=$N7k2L$O$D$.$NDL$j$G$"$C$?!#(J
$B!!!&F1 $B!!!&0[ $B!!!&NO$NBg$-$5$O$=$l$>$l$NEE2Y$N@Q$KHfNc$9$k!#(J
$B!!!&NO$NBg$-$5$O#2$D$NEE2Y$N5wN%$N#2>h$KH?HfNc$9$k!#(J
$B$3$l$r(J$B%/!<%m%s$NK!B'(J$B$H$$$$!"<0$KI=$9$H

$B!!(J

$B$3$3$G!"(Jr$B$O#2$D$NEE2Y$N5wN%!"(Jq1$B!"(Jq2$B$O$=$l$>$l$NEE2Y$G$"$k!#$^$?!"(Jk $B$OHfNcDj?t$G!"NO(JF$B$NC10L$r(JN$B!"(Jr $B$NC10L$r(Jm$B!"(Jq1$B!"(Jq2$B$NC10L$r(JC$B$H$9$k$H!"(Jk=9.0$B!_(J109 N(I%(Jm2/C2$B$H$J$k!#(JF>0$B$N$H$-$O@MNO!"(JF<0$B$N$H$-$O0zNO$rI=$7$F$$$k!#$D$^$j!"(Jq1$B!"(Jq2$B$,F1Id9f$N;~$OH?H/$79g$$!"0[Id9f$N;~$O0z$-9g$&$3$H$r<($7$F$$$k!#(J

$B!{1~MQNc!!(J
$B!!@EEE5$NO$OEE;RJ#


$B!ZNcBj(J1-1$B![(J
(1)
$B!!?eAG86;R$K$*$1$kM[;R$HEE;R$N4V$KF/$/%/!<%m%sNO$NBg$-$5$r5a$a$h!#$?$@$7!"M[;R$HEE;R4V$N5wN%$r(J5.3$B!_(J10-11m$B!"M[;R$NEE2Y$r(J1.6$B!_(J10-19C$B!"EE;R$NEE2Y$r(J-1.6$B!_(J10-19C$B!"%/!<%m%s$NK!B'$NHfNcDj?t$r(J9.0$B!_(J109N(I%(Jm2/C2$B$H$9$k!#(J

(2)$B!!?eAG86;R$K$*$1$kM[;R$HEE;R$N4V$KF/$/K|M-0zNO$NBg$-$5$r5a$a$h!#$?$@$7!"M[;R$HEE;R4V$N5wN%$r(J5.3$B!_(J10-11m$B!"M[;R$N-27k$B#g!"EE;R$N-31k$B#g!"K|M-0zNODj?t$r(J6.67$B!_(J10-11N(I%(Jm2/k$B#g(J2$B$H$9$k!#(J

$B!!(J$B2rEz(J

$B%H%C%W(J$B!!!!!!(J


$B"!EE3&(J(electric field)
$B!!N%$l$?EE2Y$HEE2Y$N4V$GNO$,F/$/$,!"EE2Y$+$iEE2Y$KD>@\NO$,EA$o$k$o$1$G$O$J$$!#EE2Y$,$"$k$H$=$N<~$j$KEE5$E*$J>l$,@8$8$F!"$3$N>l$KCV$+$l$?EE2Y$KNO$,F/$/$N$G$"$k!#$3$NEE5$E*$J>l$r(J$BEE3&(J$B!J$"$k$$$O(J$BEE>l(J$B!K$H8F$V!#EE3&$,2>A[E*$J$b$N$G$J$/

$B!}EE3&$NDj5A(J
$B!!EE3&$NCf$KCV$+$l$?EE2Y(Jq $B$KNO(JF$B$,F/$/$H$-!"$3$NEE3&$N6/$5(JE$B$r(J
$B!!!!!!(J
$B$HDj5A$9$k!#C10L$O(JN/C$B$H$J$k!#EE3&$N8~$-$O$=$NE@$KCV$+$l$?@5$NEE2Y$K$+$+$kNO$N8~$-$HF1$8$G$"$k!#(J
$B!!$7$?$,$C$F!"EE3&(JE$B$NCf$KEE2Y(Jq$B$rCV$$$?$H$-F/$/NO(JF$B$O(J
$B!!!!!!(J
$B$H$J$k!#(Jq$B$,@5$N$H$-$O(JF$B$O(JE$B$HF1Id9f!"$9$J$o$AEE3&$N8~$-$KNO$rq$B$,Ii$N$H$-$O(JF$B$O(JE$B$H0[Id9f$H$J$j!"EE3&$HH?BP8~$-$NNO$r $B!!Nc$($PEE2Y(JQ$B$+$i5wN%(Jr$BN%$l$?E@$NEE3&$O$I$&$J$k$G$"$m$&$+!#$3$NE@$KEE2Y(Jq $B$rCV$$$?$H$-!"%/!<%m%s$NK!B'$h$j(J
$B!!!!(J
$B$NNO$,2C$o$k$+$i!"EE3&$N6/$5(JE$B$O!"(J
$B!!!!(J
$B$H$J$k!#(J


$B!ZNcBj(J1-2$B![(J
$B?eAG86;R$K$*$$$FEE;R$N0LCV$G$NEE3&$NBg$-$5$r5a$a$h!#$?$@$7!"M[;R$HEE;R4V$N5wN%$r(J5.3$B!_(J10-11m$B!"M[;R$NEE2Y$r(J1.6$B!_(J10-19C$B!"%/!<%m%s$NK!B'$NHfNcDj?t$r(J9.0$B!_(J109N(I%(Jm2/C2$B$H$9$k!#(J

$B2rEz(J


$B!ZNcBj(J1-3$B![(J
x$B$N@5$N8~$-$K(J2.0$B!_(J104N/C$B$NEE3&$,$+$+$C$F$$$k$H$3$m$K!"(J-1.6$B!_(J10-19C$B$NEE;R$rCV$$$?!#(J
(1)$B!!EE;R$K$O$I$A$i8~$-$NNO$,$+$+$k$+!#(J
(2)$B!!EE;R$K$+$+$kNO$NBg$-$5$O$$$/$i$+!#(J

$B2rEz(J


$B!}EE5$NO@~(J(line of electric force)
$B!!EE3&$r?^<($9$k$N$K!"EE3&$N8~$-$K1h$C$F@~$rO"$M$?$b$N$,;H$o$l$k!#$3$l$r(J$BEE5$NO@~(J$B$H$$$&!#$D$^$j!"$3$N6J@~>e$N3FE@$N@\@~$O$=$NE@$NEE3&$N8~$-$rI=$7$F$$$k!#EE3&$OEE2Y$N$J$$$H$3$m$GFMA3@8$8$k$?$j>CLG$7$?$j$9$k$3$H$O$J$$$N$G!"EE5$NO@~$bEE2Y$N$J$$$H$3$m$GES@Z$l$k$3$H$O$J$$!#$^$?EE3&$N8~$-$OI,$:0lJ}8~$K7h$^$k$N$G!"EE5$NO@~$N@\@~$N8~$-$b>o$K#1$D$K7h$^$j!"EE5$NO@~$,8r$o$k$3$H$O$J$$!##1$D$NEE2Y$NNc$r2<$K<($7$?!#$3$l$r8+$F$bJ,$+$k$H$*$j!"EE3&$N6/$$$H$3$m$G$OEE5$NO@~$NL)EY$,Bg$-$/$J$C$F$*$j!"EE5$NO@~$GEE3&$N8~$-$@$1$G$J$/6/$5$bI=$;$k$3$H$,$o$+$k!#(J

$B!}#18D$NEE2Y$,$"$k$H$-$NEE5$NO@~(J


$B!ZNcBj(J1-4$B![(J
$B$D$.$N>l9g$KEE5$NO@~$O$I$N$h$&$K$J$k$+!#2JN,$7$F$"$k!#(J
(1)$B!!(JQ (Q >0)$B$H(J-Q$B$NEE2Y$rJB$Y$?$H$-(J
(2)$B!!(JQ (Q >0)$B$NEE2Y$r#2$DJB$Y$?$H$-(J

$B!!!!!!!!!!!!!!!!!!(J(a)$B!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!(J(b)

$B2rEz(J

$B%H%C%W(J

$B!J;29M!'#28D$NEE2Y$K$h$kEE5$NO@~$rIA$/%=%U%H$N%@%&%s%m!<%I$O(J$B$3$A$i(J$B!#(J
$B!!!!!!!!$"$^$j%(%l%,%s%H$G$O$"$j$^$;$s$,!"$h$m$7$+$C$?$i;H$C$F$_$F$/$@$5$$!#(J
$B!!!!!!!!%(%/%;%k$N%U%!%$%k!N4^%^%/%m!O$G$9!#!K(J
$B!!!!!!(J


$B"!EE0L(J(electric potential)

$B!!e$2$k$N$K$O;E;v$rMW$9$k!#K`;$$,L5;k$G$-$k$H$-!"$3$N$H$-$N;E;v(JW$B$O!"J*BN$Nm$B!"=ENO2CB.EY$r(Jg$B!";}$A>e$2$k9b$5$r(Jh$B$H$9$k$H!"(JW=mgh$B$HI=$5$l$k!#$D$^$j=ENO2CB.EY$,0lDj$N$H$-!";E;v$NBg$-$5$Oh$B$K$"$kJ*BN$O!"Mn$A$k$^$G$K;}$A>e$2$k$N$KMW$7$?$N$HF1$8Bg$-$5$N;E;v$r$9$k$3$H$,$G$-$k$N$G!"(Jmgh$B$N(J$B0LCV%(%M%k%.!<(J$B;}$C$F$$$k$3$H$K$J$k!#(J
$B!!$5$F!"EE3&(JE$B$NCf$KCV$+$l$?EE2Y(Jq$B$r$3$l$KF/$/NO$K5U$i$C$F5wN%(Jd $B$@$1F0$+$9$K$O!"$d$O$j;E;v$,I,MW$G$"$k!#$3$N$H$-$N;E;v(JW$B$O(JW=qEd$B$H$J$j!"F0$$$?8e$NEE2Y$O$3$l$@$1$N0LCV%(%M%k%.!<$,A}$($k!#$3$3$G!"(J

$B!!!!(JV=Ed

$B$HCV$/$H!"(JW=qV$B$H$J$k!#l9g$HHf3S$9$k$H!"E$B$,AjEv$7$F$$$k!#$=$7$FV$B$r(J$BEE0L:9(J$B$"$k$$$O(J$BEE05(J$B$H$$$&!#(J1C$B$NEE2Y$r0\F0$9$k$N$K(J1J$B$N;E;v$,I,MW$JEE0L:9$,(J1V$B!J%\%k%H!K$G$"$k!#$^$?!"3$LL$+$i$N9b$5$rFC$KI89b$H$$$&$h$&$K!"$"$k4p=`E@$+$i$NEE0L:9$r(J$BEE0L(J$B$H$h$V!#(J


$B!ZNcBj(J1-5$B![(J
X$B@~4I$NCf$N(J2.0 cm$BN%$l$?#2$D$NEE6K$K(J24 kV$B$NEE05$r$+$1$?!#EE6K4V$NEE3&$N6/$5$O$I$N$/$i$$$+!#(J

$B2rEz(J


$B!ZNcBj(J1-6$B![(J
$BMkEy$N$?$a$KCO5e$OIi$KBSEE$7$F$$$k!#$=$N$?$aCOI=IU6a$G$O$*$h$=(J100N/C$B$N2<8~$-$NEE3&$,$"$k!#(J
$BCOLL$HCO>e(J12m$B$NE@$NEE0L:9$O$I$N$/$i$$$+!#(J

$B2rEz(J


$B!}EyEE0L@~(J(equipotential line) $B!!!!!!(J
$B!!(J
$BCO7A$rI=$9$N$K!"F1$8I89b$NE@$rO"$M$?Ey9b@~$,MQ$$$i$l$k!#F1MM$K!"EE3&$N$h$&$9$r<($9$?$a$KF1$8EE0L$NE@$rO"$M$?@~$,MQ$$$i$l$k!#$3$N@~$N$3$H$r(J$BEyEE0L@~(J$B$H$h$V!#Ey9b@~$N4V3V$,69$$$H$3$m$OJ}8~$,J}8~$,EE3&$NJ}8~$H$J$C$F$$$k!#$7$?$,$C$FEE5$NO@~$HEyEE0L@~$OD>8r$9$k!#(J

$B!J;29M!'EyEE0L@~$rIA$/%=%U%H$N%@%&%s%m!<%I$O(J$B$3$A$i(J$B!#%(%/%;%k$N%U%!%$%k!N4^%^%/%m!O$G$9!#(J
$B!!!!!!!!(J3D$BHG$O(J$B$3$A$i(J$B$G$9!#!K(J


$B!ZNcBj(J1-7$B![(J
(a)
$B!!(JQ (Q >0)$B$H(J-Q$B$NEE2Y$rJB$Y$?$H$-!"EyEE0L@~$O$I$N$h$&$K$J$k$+!#(J

(b)$B!!(JQ (Q >0)$B$NEE2Y$r#2$DJB$Y$?$H$-!"EyEE0L@~$O$I$N$h$&$K$J$k$+!#(J

$B2rEz(J

$B%H%C%W(J$B!!!!!!(J


$B"!$^$H$a(J

$B!{%/!<%m%s$NK!B'(J
$B!!!!(J

$B!{EE3&Cf$NEE2Y$, $B!!!!(JF=qE

$B!{EE0L(J
$B!!!!(J
V=Ed


$B1i=,LdBj2rEz(J

$B%W%j%s%H%@%&%s%m!<%I(J$B!&!&!&(J2003$BG/EY$N9V5A$GG[I[$7$?%W%j%s%H$N(Jpdf$B%U%!%$%k$G$9!#(J

$BJ*M}9V5A0lMw$X$b$I$k(J

$B!!(J