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Active Contributor

Join Date: Mar 2007
Posts: 16

# cylindrical magnet

07/13/2007 1:28 AM

hello everybody

i am working on a project in which 2500 N force is required to be imparted by a magnet or number of magnets in series.i inquired one shop which gave me the details that 35mm dia,24mm thickness magnet would impart 10000gauss magnetic fiels.Now, i am unable to find the force which this would impart, so that i could use it for my project.

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Guru

Join Date: Jul 2006
Location: Silicon Valley
Posts: 5356
#1

### Re: cylindrical magnet

07/14/2007 12:19 AM

They've given you the flux density of the magnet. Go back and ask them for the force which the magnet is capable of.

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Guru

Join Date: Jun 2007
Posts: 1035
#2

### Re: cylindrical magnet

07/14/2007 10:46 AM

Granted, they gave the flux density since the size of the magnet was known, and the field strength was given. But remember, not ALL permanent magnets of that particular size will afford the same field strength. The flux density is a function of the permeability and retentivity of the material (among other things). Read the Wikipedia article ('shudder') for starters ... it's not bad:

http://en.wikipedia.org/wiki/Magnetic_field

Perhaps I've "slipped", and forgotten a fundamental here (will research back in office on Monday), but, I don't believe the force can be calculated without knowing a few factors about the object being acted upon. Putting it simply, the magnet of which you speak, if brought into proximity with a piece of crown glass will exert or impart a force much much less than if brought close to a tool steel bar, which will likewise be less than if it is brought up to a soft iron rod such as a solenoid core.

Anyone else out there heavily into the numbers of same...(?) {Help!}

Guru

Join Date: Jun 2007
Posts: 1035
#3

### Re: cylindrical magnet

07/14/2007 10:55 AM

"PS"

Go to :

and scroll down to "Magnetism" converters ... just for fun.

Guru

Join Date: Jul 2006
Location: Silicon Valley
Posts: 5356
#4

### Re: cylindrical magnet

07/15/2007 12:58 AM

Very interesting!!!

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"Perplexity is the beginning of dementia" - Professor Coriolus
Anonymous Poster
#5

### Re: cylindrical magnet

07/16/2007 10:52 AM

Doesn't the force also depends on what the magnet will be attracting to?

Pineapple

Anonymous Poster
#6

### Re: cylindrical magnet

07/16/2007 4:14 PM

I suspect that this is exactly what the poster meant in #2, above:

"Putting it simply, the magnet of which you speak, if brought into proximity with a piece of crown glass will exert or impart a force much much less than if brought close to a tool steel bar, which will likewise be less than if it is brought up to a soft iron rod such as a solenoid core."