To make a solenoid, you need a hollow cylinder, a battery and lots of conducting wire. The wire must be wound dozens of times around the cylinder, with both ends connected to a battery. This allows the current to flow, replicating the effect of a bar magnet.
- Gather your materials
Determine the size of your solenoid, and arrange for materials accordingly. For a hollow cylinder, arrange for something similar to the cardboard of a toilet roll. Length of the conducting wire should be adequate for three to four dozen winds around the cylinder. Get a battery of an appropriate voltage. In this case, a 5-volt should work fine.
- Wind the wire around the cylinder
Wind the conducting wire in tight, close packing around the cylinder around 40 to 50 times. The ends of the wire should be left loose to connect to the battery.
- Complete the circuit, and test the solenoid
Attach one end of the wire to the positive and one end to the negative terminal of the battery. To test the solenoid, lower a piece of conducting metal or a magnet into the cylinder. Due to the induced magnetic field of the solenoid, the metal piece or magnet should be seen moving inside the cylinder.