etElementById) x=document.getElementById(n); return x; } function MM_nbGroup(event, grpName) { //v3.0 var i,img,nbArr,args=MM_nbGroup.arguments; if (event == "init" && args.length > 2) { if ((img = MM_findObj(args[2])) != null && !img.MM_init) { img.MM_init = true; img.MM_up = args[3]; img.MM_dn = img.src; if ((nbArr = document[grpName]) == null) nbArr = document[grpName] = new Array(); nbArr[nbArr.length] = img; for (i=4; i < args.length-1; i+=2) if ((img = MM_findObj(args[i])) != null) { if (!img.MM_up) img.MM_up = img.src; img.src = img.MM_dn = args[i+1]; nbArr[nbArr.length] = img; } } } else if (event == "over") { document.MM_nbOver = nbArr = new Array(); for (i=1; i < args.length-1; i+=3) if ((img = MM_findObj(args[i])) != null) { if (!img.MM_up) img.MM_up = img.src; img.src = (img.MM_dn && args[i+2]) ? args[i+2] : args[i+1]; nbArr[nbArr.length] = img; } } else if (event == "out" ) { for (i=0; i < document.MM_nbOver.length; i++) { img = document.MM_nbOver[i]; img.src = (img.MM_dn) ? img.MM_dn : img.MM_up; } } else if (event == "down") { if ((nbArr = document[grpName]) != null) for (i=0; i < nbArr.length; i++) { img=nbArr[i]; img.src = img.MM_up; img.MM_dn = 0; } document[grpName] = nbArr = new Array(); for (i=2; i < args.length-1; i+=2) if ((img = MM_findObj(args[i])) != null) { if (!img.MM_up) img.MM_up = img.src; img.src = img.MM_dn = args[i+1]; nbArr[nbArr.length] = img; } } } //-->

LA BIELLE

Matériel nécessaire: perle-planchette,des clous.

Réalisation: On a pris deux boîtes et une lame de sie à métaux;

Ce qu'on observe: les boites ne tournent pas dans le même sens