cool experiment - Page 1
Forum section: electronics / general

author: robrenz
author_rank: Super Contributor
timestamp: August 23, 2012, 11:18:04 am
content: Notice the optically distorted image around the wire from the heat starting around 2:40. Nice demonstration.

author: cookie
author_rank: Contributor
timestamp: September 01, 2012, 02:58:54 pm
content: so cool

author: saturation
author_rank: Super Contributor
timestamp: September 01, 2012, 04:05:37 pm
content: Nice. If you have an old hard drive anywhere and want a good magnet, the drive heads use Neodymium magnets. Tearing the old HD apart is also one way to insure better security for your data before being discarded. The drive platens are so polished and smooth, they make good metal camping or travel mirrors.

author: G7PSK
author_rank: Super Contributor
timestamp: September 01, 2012, 05:51:52 pm
content: The last hard drive I took apart the platters were made of glass.

author: ablacon64
author_rank: Frequent Contributor
timestamp: September 01, 2012, 06:56:37 pm
content: Very interesting!

author: johnmx
author_rank: Frequent Contributor
timestamp: September 01, 2012, 08:46:38 pm
content: The first effect happens every day around us. Take a picture of a hi-voltage power line during a hot day and take another one in a cold day. Superimpose both pictures and see for yourself the difference.

author: sorin
author_rank: Frequent Contributor
timestamp: September 02, 2012, 12:22:38 am
content: THANKS FOR SHARING

author: free_electron
author_rank: Super Contributor
timestamp: September 02, 2012, 02:22:32 am
content: Be carefull with drive magnets !When you pry the magnet off from around the voice coil you are not really holding the magnet but the magnetic loop trap. There is typically a u shaped piece and a flat piece. These two combined create the magnetic loop. The magnet itself is a little silvery slab of meterial held to the u shaped piece or to the flat piece.The magnet material is very brittle. If you take it off the loop : do NOT bring two bare magnets in close proximity to each other. They will jump towards each other and the impact force will shatter the material. Splinters of this material may fly off. Get them in your eyes ... You know the problem...

author: Psi
author_rank: Super Contributor
timestamp: September 02, 2012, 03:01:28 am
content: Magnets!, the big ones can break your arm.I'm serious, one of these huge rare earths can shatter bones on impact.

author: T4P
author_rank: Super Contributor
timestamp: September 02, 2012, 03:46:28 am
content: IIRC, neodymium have the best weight/size ratio on earth

author: saturation
author_rank: Super Contributor
timestamp: September 02, 2012, 02:28:39 pm
content: ...or aluminum or some composite ceramic, but regardless the alloy deposited on the surface makes a shiny surface, and tough as a mirror. So far it hasn't sloughed off with use in hot and humid climates.Quote from: G7PSK on September 01, 2012, 05:51:52 pm

author: sorin
author_rank: Frequent Contributor
timestamp: September 03, 2012, 02:52:51 pm
content: Quote from: Psi on September 02, 2012, 03:01:28 amhave you done some calculations, to say this, or is just your opinion?

author: AntiProtonBoy
author_rank: Frequent Contributor
timestamp: September 03, 2012, 02:58:12 pm
content: Depends what bones we're talking about. One thing's for sure, these puppies have no problem mushing your finger tips into meat paste.http://gizmodo.com/5156490/guy-loses-a-chunk-of-his-finger-in-neodymium-magnet-accident-nsfw

author: grenert
author_rank: Frequent Contributor
timestamp: September 03, 2012, 03:18:52 pm
content: Quote from: robrenz on August 23, 2012, 11:18:04 amI think those are called Schlering (sp?) lines.

author: rolycat
author_rank: Super Contributor
timestamp: September 03, 2012, 04:10:18 pm
content: Quote from: grenert on September 03, 2012, 03:18:52 pmSchlieren lines, caused by refraction of light due to its higher speed in the less dense heated air. (As any fule kno)

author: T4P
author_rank: Super Contributor
timestamp: September 03, 2012, 06:18:44 pm
content: No need to do calculations, i get scared looking at the larger ones

author: lapm
author_rank: Frequent Contributor
timestamp: September 03, 2012, 07:14:11 pm
content: I have had some fun on small magnets salvaged from broken cd writer stations. Main lens assembly that turns that small lens seems usually have small but strong magnets.. If i only could thing something more usefull then noteholding on side of metal cabin for those to use.

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 04, 2012, 12:48:22 pm
content: Quote from: T4P on September 02, 2012, 03:46:28 amare you kidding? or the best troll?

author: G7PSK
author_rank: Super Contributor
timestamp: September 04, 2012, 03:45:58 pm
content: Quote from: AntiProtonBoy on September 03, 2012, 02:58:12 pmMost likely the due to the speed and mass than the actual strength of magnet. I one came across a horseshoe magnet that came from a radar set, it was so strong that it would lift a full size oxygen cylinder, unfortunately I could not persuade the owner of the scrap yard who had it to sell, I suppose that that magnet would break your leg, if the cylinder fell onto it.

author: T4P
author_rank: Super Contributor
timestamp: September 04, 2012, 05:37:00 pm
content: Quote from: Mechatrommer on September 04, 2012, 12:48:22 pmErm, I don't know ... i think i actually meant worst weight/size ratioStrong and heavy ...anything heavier per sq-inch?

author: merlinb
author_rank: Contributor
timestamp: September 04, 2012, 08:23:28 pm
content: Quote from: Psi on September 02, 2012, 03:01:28 amI didn't know Chuck Norris made magnets.

author: SeanB
author_rank: Super Contributor
timestamp: September 04, 2012, 08:40:50 pm
content: I respect any magnet stronger than ALNICO, as they are both brittle and high power. Big ferrite magnets are also dangerous.

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 05, 2012, 03:44:15 am
content: Quote from: T4P on September 04, 2012, 05:37:00 pmosmium or iridium are densest element according to this chap...http://chemistry.about.com/od/elementfacts/f/densest-element.htmor Hassium...http://chemistry.about.com/od/elementfacts/a/elementdensity.htmmany other heavier elements one example Nobelium (No) based on periodic table...http://www.webelements.com/and many many other elements lighter and less dense than Nd. so what do you mean? i guess you meant highest magnetic force/weight? or force/size (volume)?...nitpicker...