EField4 Physics Example:  Potential Energy

Three unknown charged objects are shown on the screen along with their potential energy.  You can click-drag on any charge to change its position.  How many objects have like charge?  Can you rank the objects based upon their charge if you assume charge 1 is positive?  Start

Script

<script language="JavaScript"> 
function forces(){

document.EField.setAutoRefresh(false);
document.EField.setDefault();
document.EField.setShowTime(false);
document.EField.setShowForce(false);

id=document.EField.addObject("charge","x=-2,y=0,q=3");
document.EField.setRGB(id,0,0,0);
tid=document.EField.addObject("text","text=U1=,calc=p");
document.EField.setDisplayOffset(tid,-22,-20);
document.EField.setAnimationSlave(id,tid);

id=document.EField.addObject("charge","x=2,y=0,q=-2");
document.EField.setRGB(id,0,0,0);
tid=document.EField.addObject("text","text=U2=,calc=p");
document.EField.setDisplayOffset(tid,-22,-20);
document.EField.setAnimationSlave(id,tid);

id=document.EField.addObject("charge","x=0,y=2,q=2");
document.EField.setRGB(id,0,0,0);
tid=document.EField.addObject("text","text=U3=,calc=p");
document.EField.setDisplayOffset(tid,-22,-20);
document.EField.setAnimationSlave(id,tid);

document.EField.setAutoRefresh(true);

}
</script>