To understand the theory of electromagnetic motors. watch opening 3 minutes of this video
C or D Battery (1pcs)
1m of solid core copper wire
Iron all thread M6 or larger.
Step 1: Wrap the Copper Wire Around the All-thread and Close Off the Ends With Insulation Tape
Step 2: Connect the Battery to the Ends of the Wire
Step 3: Test Out Your Inductor on a Compass and Some Nails
Your inductor should be a temporary magnet as long as the wire is connected to the battery.