In an experiment I am carrying out I am levitating metal rings using a solenoid with a clamp stand going through the solenoid acting as a support for the ring and a core for the solenoid (seen in the attachment). I have one simple question? Theorectically, should an Aluminium or Copper ring levitate higher (at a fixed current through solenoid) ? Would any other factors like ring diameter etc. affect the height of levitation (I am keeping the voltage/current constant)? Thanks in advance!