Card with copper rod going through middle. Iron filings scattered on card round rod. I pass 8A via an ammeter through rod, but filings scarcely align in the magnetic field at all. (I do tap the card). Can anyone suggest how I could improve the result (e.g. get three separated concentric rings of filings). Thanks
Magnetic field round current-carrying conductor
- Thread starter Strike3
- Start date
Elizabeth Gould
COMMITTEE
I second this. A much more noticeable result.
Thanks for replies. Yes, the compasses are better, but not as impressive. I thought my iron filings might be a bit heavy (not fine enough, or a bit damp). I notice that the "demonstrations" on youtube are mostly simulations, so perhaps the experiment doesn't really work so well in practice.
These are an alternative to consider, I see them as somewhere in between iron filings and plotting compasses:
They work nicely on an Overhead Projector too. No mess, no realigning compasses.
They work nicely on an Overhead Projector too. No mess, no realigning compasses.
Ooh, we've got some of those, I've never thought of using them for this demo. Thanks !
Peter Sigsworth
COMMITTEE
Looks really good but a bit expensive @ over £20 each
We paid £20 for a set of 4, I think that's what they mean even though it says 'each'.
It's unclear though, as is often the case on the suppliers websites..
Peter Sigsworth
COMMITTEE
I've spoken to SciChem then image shown is from another manufacturer. SciChem say they supply three in their kitWe paid £20 for a set of 4, I think that's what they mean even though it says 'each'.
It's unclear though, as is often the case on the suppliers websites..
Wow, blimey well I guess that's inflation then.
Or..
You could shop around...
www.science2education.co.uk
www.betterequipped.co.uk
www.philipharris.co.uk
All doing 4 for £20-ish
(And one is doing 4 for £42!)
Or..
You could shop around...
SLS Select Education | School Science Equipment
We are a division of Scientific Laboratory Supplies Ltd, specialising in school science equipment. Shop online, or contact a member of our friendly team today.
Magnetic Field Demonstrator x4 Plates [1002]
Ever tried removing iron filings from a magnet? This is the perfect solution for previously-messy magnetic field line demonstrations, clearly revealing the field lines in 1, 2 or 3 dimensions with ...
www.betterequipped.co.uk
Magnetic Field Demonstrator
The Magnetic Field Demonstrator comprises a set of four transparent plastic plates 153 x 76 x 6mm, each plate has a matrix of 98 (14 x 7) small circular chambers, each chamber containing an iron rod and functioning effectively as a plotting compass. The plates may be arranged in various ways...
www.philipharris.co.uk
All doing 4 for £20-ish
(And one is doing 4 for £42!)
We have plotting compasses glued to a Petri dish with the wire threaded through the middle.
Peter Sigsworth
COMMITTEE
@Strike3 .Ok had a play to see if I can get the iron filings to work.
Using a Unilab13V, 8.5 A, Bench Power Unit (from Philip Harris)
Set to 4 volts DC (cuts out any higher) through a bench ammeter and 1 metre of PVC coated wire 0.6mm diameter.
Cut a piece of cardboard 12cm2 and cut a 0.5 cm hole in the middle using a cork borer. Then, to make the filings move easier, I put a sheet of clear OHP acetate sheet of the same size over the card, fed the wire through and sprinkled fine iron filings over the surface to get this:
The next trick was to get an old Oral-B electric toothbrush without the brush head switch on the power and touch the side of the card whilst holding it steady. The vibrations sorted the problem and allowed the filings to move as the two images below:
The black line is a shadow of the green wire.
Not spectacular but the toothbrush works.
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I like the ingenious use of an electric toothbrush.
you can use them for standing waves as well.