how do u make an electromagnet?
An electromagnet is basically a coil of wire. You can make it stronger by putting a soft iron core in your coil, increasing the number of loops, and increasing the current going around the coil. Where B is the magnetic field, mu is the permeability of the core, N is the number of turns per unit length, I is the current, and L is the length of coil. Most magnets saturate at 1-2 teslas, they are investing in 7T magnets for use in PET scanning, this is achieved with liquid helium (i think) cooling.
