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# Equal surface fields? Different pull forces?

## Equal surface fields? Different pull forces?

(OP)

Magnet Length Width Thickness Surface Field Pull FORCE
(Gauss) (LB)

B444 1/4 " 1/4 " 1/4 " 5754 4.25
B666 3/8 " 3/8 " 3/8 " 5754 10.07
B888 1/2 " 1/2 " 1/2 " 5754 18.71
BCCC 3/4 " 3/4 " 3/4 " 5754 40.59
BX0X0X0 1 " 1 " 1 " 5754 76.41

What explains this?
Is the attraction force determined from the surface field?
A larger magnet would have the equal value fore the surface field but a stronger attraction/repulsion force?!

### RE: Equal surface fields? Different pull forces?

(OP)
The pull force is next to the surface field (5754)
The force is in (lb).

### RE: Equal surface fields? Different pull forces?

Physics.

The surface field is a flux density. The total flux is a product of the density and the area of the face.

https://en.wikipedia.org/wiki/Magnetic_flux

### RE: Equal surface fields? Different pull forces?

(OP)
What? I have no idea what you ment RyreInc
However, I seem to noticed that the force is dependent on the area, the larger the area the more space the flux line can pass and the force is greater.

### RE: Equal surface fields? Different pull forces?

(OP)
I also noticed that,
When the surface area of the magnet is = to the surface area of the other magnet or magnetic object, the magnetic force of attraction/repulsion is at its heights.

(OP)
Its greatest*

### RE: Equal surface fields? Different pull forces?

(OP)
Is it safe to say, to utilize a magnets full force at a gap of 0... The area should be = or greater to the magnets area?

### RE: Equal surface fields? Different pull forces?

One more thing, i would also like to mention in addtion to the reply in your other post. The magnetic force of attaction & repulsion will vary w.r.t the surface area of the magnet. If you have 2 different sized magnet with different volume or if same sized magnet with different magnetic material.

The force tend to change between magnet

### RE: Equal surface fields? Different pull forces?

Hey ndsram,
The force between the magnets is a lot more complicated than what I've thought. Thats what I can say...

### RE: Equal surface fields? Different pull forces?

Dear Vis99,

It is not so, the way in which you perceive is more important. Consider what are the criteria will affect for of a magnet.
Take a simple example and get into basic understanding.Lets take steel and magnet of area 10 mm^2 of both and volume be 1000 mm^3

Here are few
Distance between the magnet and steel

Set ideal condition to compute force then try with diffrent option by varying parameters which you're interested

Reg
N D Ssenthil Ram

### RE: Equal surface fields? Different pull forces?

Hey ndsram,

I just noticed, that when I bought te magnets. They are rated at 5lb of force maximum.
I discovered, in order to get that MAX. force of 5lb the object has to be strongly magnetic and the surface area where the force is applied has to be equal to the magnet or greater and you find that force to be significant!

### RE: Equal surface fields? Different pull forces?

Ow yea also how thick that magnetic object is is important to utilize the MAXIMUM force.

### RE: Equal surface fields? Different pull forces?

BY converging or diverging the flow of flux lines in a steel, the holding force may be determined. Try to see some example of holding magnet

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