1000 SCREEN 12:CLS:?:PRINT" ELECTRIC STRENTH LINES"
1001 PAINT(0,0),8
1002 DIM Q(3),X(4),Y(4),R(3),E(4),A(4),B(4)
1003 PI=4*ATN(1):KQ=1:KY=((800)/(3*640))*(480/200):REM KY=.41666
1004 X(1)=160:Y(1)=180/KY
1005 X(2)=500:Y(2)=240/KY
1006 X(3)=280:Y(3)=220/KY
1008 Q(1)=36*KQ
1009 Q(2)=36*KQ
1010 Q(3)=-20*KQ
1012 G=10
1013 L=10
1014 SM=1000
1021 FOR N=1 TO 3
1022 IF SGN(Q(N))>0 THEN CV=12 ELSE CV=9
1023 CIRCLE(X(N),KY*Y(N)),G:PAINT (X(N),KY*Y(N)),CV:CIRCLE(X(N),KY*Y(N)),G,0
1024 NEXT N
1032 FOR N=1 TO 2
1034 DF=(2*PI)/Q(N)
1040 FOR F=0 TO (2*PI) STEP DF
1041 S=0
1042 X(4)=X(N)+G*(1.1)*COS(F)
1044 Y(4)=Y(N)+G*(1.1)*SIN(F)
1045 PSET(X(4),KY*Y(4))
1050 FOR J=1 TO 3
1052 RX=X(4)-X(J)
1053 RY=Y(4)-Y(J)
1054 R(J)=SQR(RX*RX+RY*RY)
1056 E(J)=Q(J)/(R(J)*R(J))
1058 A(J)=E(J)*(X(4)-X(J))/R(J)
1059 B(J)=E(J)*(Y(4)-Y(J))/R(J)
1061 NEXT J
1062 A(4)=A(1)+A(2)+A(3)
1064 B(4)=B(1)+B(2)+B(3)
1066 E(4)=SQR(A(4)*A(4)+B(4)*B(4))
1068 LX=L*A(4)/E(4)
1070 LY=L*B(4)/E(4)
1071 S=S+L
1072 X(4)=X(4)+LX
1074 Y(4)=Y(4)+LY
1076 DR3=SQR((X(3)-X(4))*(X(3)-X(4))+(Y(3)-Y(4))*(Y(3)-Y(4)))
1077 DR3=INT(DR3)
1078 IF DR3<=(G-1) THEN GOTO 1084
1080 IF S>SM THEN GOTO 1084
1082 LINE-(X(4),KY*Y(4)),7
1083 GOTO 1050
1084 NEXT F
1086 NEXT N
 SOUND 3000,.3
WATA:
 IF INKEY$=CHR$(27) THEN STOP ELSE WATA