Ferrite Bar Magnets

Ferrite bar magnets for basic experiments on magnetic field lines & attraction-repulsion. Safe for children, includes lab analysis showing low to no heavy metals. Buy Indigo brand bar magnets for quality+economy.

Indigo ferrite ceramic bar magnets blue-red & stamped N-S and magnetized at the ends for repulsion-attraction. Pick up paper clips or show the shape of magnetic fields with iron filings, compasses or magnaprobes.

Displaying 1 to 4 (of 4 products)
75mm (3") Bar Magnet

75mm (3") Bar Magnet

SKU: 33544
$1.40USD or lower Each
100mm (4") Bar Magnet

100mm (4") Bar Magnet

SKU: 33540
$1.85USD or lower Each
120mm (5") Bar Magnet

120mm (5") Bar Magnet

SKU: 33543
$2.85USD or lower Each
Magnetic Field Demo

Magnetic Field Demo

SKU: 33545-SP1
$26.95USD or lower Each
More Information

How to Measure the Magnetic Field?

Here are 3 ways to use bar magnets for in a magnetic field visualization experiment. We offer material for the first two.

  • Make the magnetic field lines visible using iron filings with a petri dish or FieldView
  • Use a Mark II Magnaprobe to show that the magnetic field lines are above, below, side to side
  • Move a plotting compass around the bar magnet & watch the needle position change

What you are seeing over the bar magnet image shown below is analogous to the shape of the magnetic field around the Earth.

Magnetic Lines

 

Magnetic Field Superposition

Put two bar magnets, as NS-NS (or SN-SN) under a petri dish. Sprinkle some iron filings over the ends of the magnets & the gap in between. Then move them towards each other & back. You should see similar magnetic field lines form in what is called superpositioning or vector addition of their respective magnetic fields.

Overlapping Magnetic Fields

Additional Information

Our blog, Ferrite Bar Magnet Experiments for Kids has additional suggestions for using bar magnets. 

You can watch an older, pre HD, video of the magnaprobe in action & how it illustrates the 3D nature of magnetic fields; a great analogy for the Earth's magnetic field.

Technical
Ferrite Cermaic Magnet Technical Specifications - C5 Grade
Grade Name Br (Kg) HcB (KOe) Hci (KOe) BhMax (MGOe) Tmax
C5 3.8 2.4 2.5 3.4 250oC
 
  • Use for repulsion-attraction
  • Will not demagnetize when pushed together
  • Stamped "N" & "S" & painted red & blue respectively
  • Paint is guaranteed to have low lead & heavy metal levels
  • Will pick up minimum of 20 uncoated metal paperclips
  • Note (1): Ferrite bars are fragile/brittle. Do not drop on hard floors.
  • Note (2): Ferrite bars are relatively weak. Us a larger neodymium rare earth disc magnets or this application.
Instructions/Safety

These magnets are very weak so there is no danger from 2 of them coming together in an attraction experiment. There are also safe for young children, supervised of course. You can view this report on Paint Analysis that shows the levels of heavy metals are well below recommended limits.