Physlet Connections: Two Charge Oscillator

Start

Two identical positive charges are placed on either end of a long skinny box.  A negatively charged 20 gr. bead is placed inside the box.  Find the charge on the bead.  You can drag the bead to any position before you begin the animation.

Show Potential

function initEField(){
     document.EField.setAutoRefresh(false);
     document.EField.setDefault();
     document.EField.setShowFieldVectors(false);
     id=document.EField.addBox(0, 0, 300, 30 );
     document.EField.setRGB(id,128,128,128);

     document.EField.setNoDrag(1);
     document.EField.setChargeRGB(0,0,0);
     document.EField.addCharge(-3.5,0,5);
     document.EField.addCharge(3.5,0,5);
     document.EField.setNoDrag(0);
     document.EField.setChargeRGB(0,255,0);
     cid=document.EField.addTestCharge(-2,0,0,0);
     document.EField.setShowFVector(cid,false);
     document.EField.setShowFComponents(cid,false);
     document.EField.setOnScreenSize(cid,10); 
     document.EField.setConstrainY(cid,0,-3,3);
     document.EField.setShowConstraintPath(cid,false); 
     document.EField.setAutoRefresh(true);


     document.DataGraph.setAutoscaleX(true);
     document.DataGraph.setAutoscaleY(true);
     document.DataGraph.setMinMaxX(0,10.0);
     document.DataGraph.clearSeries(1);
     document.DataGraph.setSeriesStyle(1,true,0);
     document.DataGraph.setLabelX("Time");  
     document.DataGraph.setLabelY("Acceleration_x");  
     document.DataGraph.setLastPointMarker(1,true);  
     document.DataGraph.setTitle("Acceleration_{x} vs. Time");  
     gid=document.DataGraph.getGraphID();

     conid=document.EField.makeDataConnection(cid,gid,1,"t","r"); 
     document.EField.forward();    
}