building potentiometers and resistors

Step 4: Why does this happen

in  electronics the resistance of a meterial depends on 3 tngs

                                  the type of matrerial
                                  the tempreture of the material
                                  this size of the material

 and since we are keeping to vairabels constent and controlling the third we can controll the materials resistance.

i chose carbon graphite because carbon is not a metal, which is very condutive. it is a but it is one of the very few non-metals that is partialy conductive and this is what we are using in our favour