10 REM PROGRAM NAME = FIELDS, SCALAR GRAVITATIONAL P. E. FIELD 20 DIM B$[10],N$[10] 30 N$="123456789" 40 PRINT "DO YOU WANT INSTRUCTIONS FOR RUNNING FIELDS? "; 50 ENTER 200,W,B$ 60 PRINT '13 70 IF B$="YES" THEN 100 80 IF B$#"NO" THEN 40 90 GOTO 230 100 PRINT 110 PRINT "THIS PROGRAM CONSTRUCTS A SIMULATED GRAVITATIONAL POTENTIAL ENERGY" 120 PRINT "FIELD, A SCALAR FIELD SINCE THE POTENTIAL ENERGY HAS MAGNITUDE" 130 PRINT "BUT NOT DIRECTION. YOU CAN INPUT THE NUMBER, SIZE, AND POSITION" 140 PRINT "OF THE MASS OR MASSES WHICH WILL ACT AS SOURCES FOR THE FIELD." 150 PRINT 160 PRINT "TO GET THE MAGNITUDE OF THE GRAVITATIONAL POTENTIAL ENERGY " 170 PRINT "AT VARIOUS POINTS, INPUT THOSE (X,Y) COORDINATES." 180 PRINT "USE NUMBERS BETWEEN 1 AND 30 FOR THE X AND Y COORDINATES." 190 PRINT 200 PRINT "IF YOU PLOT ON GRAPH PAPER THE GRAVITATIONAL POTENTIAL ENERGY AT" 210 PRINT "EACH OF YOUR COORDINATE POINTS, YOU WILL HAVE A MAP OF THE SCALAR" 220 PRINT "FIELD" 230 PRINT 240 PRINT "HOW MANY SOURCES DO YOU WANT TO USE? "; 250 ENTER 200,W,S 260 PRINT '10 270 FOR N=1 TO S 280 K2=30 290 PRINT 300 PRINT "----- SOURCE "N$[N,N]":" 310 PRINT "INPUT THE (X,Y) COORDINATES(METERS) OF SOURCE "N$[N,N]":" 320 PRINT " X = "; 330 ENTER K2,K3,X[N] 340 IF K3<0 THEN 370 350 PRINT " Y = "; 360 ENTER K2,K3,Y[N] 370 PRINT '13 380 IF K3<0 THEN 320 390 PRINT "INPUT THE MAGNITUDE(KILOGRAMS) OF SOURCE "N$[N,N]": "; 400 ENTER K2,K3,Q[N] 410 PRINT '13 420 IF K3<0 THEN 390 430 PRINT 440 NEXT N 450 PRINT '10'10 460 PRINT "TO GET THE GRAVITATIONAL POTENTIAL ENERGY AT VARIOUS POINTS," 470 PRINT "INPUT THOSE (X,Y) COORDINATES. WHEN YOU HAVE ENOUGH DATA" 480 PRINT "INPUT THE WORD DONE." 490 PRINT 500 PRINT "----- DATA TABLE:"'10 510 PRINT " COORDINATES GRAVITATIONAL POTENTIAL ENERGY" 520 PRINT " ! (ARBITRARY UNITS)" 530 PRINT "---------------------------!----------------------------------" 540 PRINT "X = "; 550 ENTER K2,K3,X 560 IF X>30 THEN 650 570 IF X<1 THEN 650 580 IF K3<0 THEN 820 590 PRINT SPA(13)"!";" Y = "; 600 ENTER K2,K3,Y 610 IF Y>30 THEN 650 620 IF Y<1 THEN 650 630 IF K3<0 THEN 820 640 GOTO 680 650 PRINT 660 PRINT SPA(5);"USE COORDINATES 1 TO 30 ONLY." 670 GOTO 540 680 GOSUB 710 690 GOTO 540 700 PRINT 710 R=0 720 FOR N=1 TO S 730 IF ( NOT (X-X[N])) AND ( NOT (Y-Y[N])) THEN 780 740 LET R[N]=SQR((X-X[N])^2+(Y-Y[N])^2) 750 R=R+Q[N]/R[N] 760 NEXT N 770 GOTO 800 780 PRINT SPA(35);"YOU ARE AT A SOURCE." 790 GOTO 810 800 PRINT SPA(27)"!";SPA(5);-INT((R+.05)*100)/100 810 RETURN 820 PRINT 830 PRINT '10'10"NOW PLOT THE INFORMATION ON GRAPH PAPER TO GET A SCALAR FIELD MAP." 840 END