Australia's Science Forum

Hi Everyone,

I was looking at buying an Arago Disk but can not find one.
Can someone please let me know where I may buy one from please.
Thanks
Superbug

WOW that's going to be a hard one to source. Ring one of the bigger company's they may be able to source one for you. Or perhaps a neighbouring school has one to could borrow. Do you have a network of Labbies near you???

Yes I do have a network of labbies nearby. but i think we prefer to have our own.
I am not even sure what it is lol

copper disk with a magnets I believe, as I said one of the larger company's can get you one I am very sure of that, but it may take until next term. We did not have one at Bonnyrigg, unless Nichole you have purchased one since I left???

In this device, a copper disk is rotated rapidly with a hand crank and a step-up pulley system. Balanced on a pivot above the center of the disk is a compass needle. The motion of the needle relative to the highly conducting copper disk induces eddy currents in the disk. In turn, these eddy currents produce a torque on the magnetic needle, which starts to rotate. The presence of eddy currents may be inferred from the fact that a copper disk with radial slots cut in it produces little effect; the slots interrupt the eddy currents.
The inverse effect also occurs: a spinning bar magnet will cause a suspended copper disk to rotate.

The French physicist, Dominique Arago (1786-1853) discovered this effect in 1825 while studying the observation that the proximity of a piece of copper to a compass needle reduces the effect of the earth's magnetic field on the needle.

The Maynooth apparatus is by Yeates & Son of Dublin, and is ca. 1877. The Smithsonian apparatus is by Queen and cost $16.50 in 1889.


St. Patrick's College, Maynooth, Ireland


Smithsonian Institution
The example at the right of Arago's Wheel from the Garland Collection of Classical Physics Apparatus at Vanderbilt University is unmarked. The copper disk is 22 cm in diameter and the compass needle is 15 cm long. The base is made of walnut.

Sorry would not take the picture, so perhaps Superbug you can google it.

I made one years ago before I was a Labby after my Mrs saw one at Uni and said she had to have one .

The bearings are from the Head Drum assemblies of some old VCRs .

Labbie wrote: Sorry would not take the picture, so perhaps Superbug you can google it.

Was something like this

yes

wow wee, thats awesome!!! Bigmack