For ages 12–16 | Materials Needed:
2 Bar magnets
Iron filings
Cardboard or white paper
Insulated copper wire
Low-voltage power supply or 6V battery
Tape (to secure items)
To see the invisible magnetic field lines of a magnet using iron filings.
Place a bar magnet under a piece of paper or cardboard.
Sprinkle a small amount of iron filings on the top surface.
Tap the paper gently with your finger or a pencil.
Watch how the filings arrange themselves.
Try it with:
One magnet
Two magnets end-to-end (North to South)
Two magnets side-by-side (North to North or South to South)
Where are the lines dense?
What happens between like and unlike poles?
✏️ Sketch one of the field patterns below:
To show that electricity can create a magnetic field.
Punch a hole in the center of a stiff cardboard or paper.
Insert a straight copper wire vertically through the hole.
Connect the ends of the wire to a 6V battery or power source.
Sprinkle iron filings gently around the wire.
Tap the board slightly and observe.
What shape do the filings make?
Are they circular around the wire?
✏️ Draw what you see:
To compare fields made by magnets and electric current.
Place a bar magnet under the paper and sprinkle filings (like in Exp. 1).
Now place a current-carrying wire under a new paper and repeat the process.
Compare the two patterns.
Which field looks stronger?
Are the shapes different or similar?
✏️ Write 2 things you noticed:
To explore how electric and magnetic fields interact.
Lay two bar magnets on a flat surface with opposite poles facing each other (like a horseshoe).
Place a current-carrying wire in between them.
Sprinkle iron filings over the setup and tap gently.
Watch how the filings form a pattern.
Are the field lines bending or changing?
Does the pattern look like any of the earlier ones?
✏️ Sketch the pattern here:
Only use low-voltage power (6V max).
Do not touch bare wires while current is flowing.
Keep iron filings away from face and eyes.
Clean up filings with a magnet wrapped in paper or a damp cloth.