Hands‑On Electromagnetism Experiment: Build and Test a Simple Electromagnet

PARTS AND MATERIALS

• 6‑volt battery
• Magnetic compass
• Small permanent magnet
• Spool of 28‑gauge magnet wire (enamel‑insulated copper)
• Large bolt, nail, or steel rod (preferably soft iron)
• Electrical tape

Magnet wire is a thin, enamel‑insulated copper wire that allows hundreds of turns to be wound into a compact coil. For an effective electromagnet, choose a magnetic core—soft iron or any readily available steel. Stainless steel is non‑magnetic and will not work.

CROSS‑REFERENCES

Lessons In Electric Circuits, Volume 1, Chapter 14: “Magnetism and Electromagnetism”

LEARNING OBJECTIVES

• Apply the left‑hand rule to determine magnetic field direction.
• Construct a functional electromagnet and observe its poles.

SCHEMATIC DIAGRAM

ILLUSTRATION

INSTRUCTIONS

1. Wrap a single layer of electrical tape around the steel core to protect the wire from abrasion.
2. Begin winding the magnet wire. Keep the coil even and maintain a consistent winding direction—never reverse from clockwise to counter‑clockwise.
3. For precision, clamp the rod in a drill press chuck and run the drill at a slow speed to feed the wire steadily. This technique ensures uniform spacing and reduces tension.
4. Continue winding until you have several hundred turns. Overlapping is acceptable; the key is uniformity.
5. Secure the finished coil with one or two layers of electrical tape.
6. Scrape the enamel insulation from both ends of the wire using a sharp knife or scissor to expose the copper for connection.
7. Connect the coil to the 6‑volt battery using jumper leads.
8. Once the current flows, the coil becomes a powerful magnet. Use the magnetic compass to identify the north and south poles at each end of the core.
9. Place a permanent magnet near one pole to observe attraction or repulsion. Flip the permanent magnet to see how the force changes.
10. To safely disconnect, never touch the coil with both hands. Use a single hand or insulated tools to avoid inductive kickback, a harmless but noticeable spark caused by the sudden interruption of current.

Electromagnets underpin many everyday devices: relays, electric motors, solenoids, doorbells, buzzers, and the magnetic heads of printers and disk drives. Understanding their operation and safety considerations is essential for any budding electrical engineer.

RELATED WORKSHEETS

• Basic Electromagnetism and Electromagnetic Induction Worksheet