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# Magnetic lateral force?

## Magnetic lateral force?

(OP)
I'm building a system that has to do with sliding magnetic fields, while the magnetic force is acting perpendicular to the applied force.
How weak is the lateral magnetic force in-comparison to the attraction force(i.e attraction force applied on a steel plate/other magnet), I know it's less, but I could not figure out how to calculate/find the magnitude of that force.

### RE: Magnetic lateral force?

(OP)
Sorry, I didn't understand what you meant by "orthogonal forces are summed"?
My question: The lateral force is weaker than the attraction force(Counter-force that acts when pulling a magnet off etc...)?
If so, how much weaker is it?

### RE: Magnetic lateral force?

Donot think one can calculate exactly the force change since the mangetization direction, the distance (and so the B), and the virtual contacting area are changing as the magnet slide along the other magnet or a steel plate.
Theoretically, if your direction of magentization (DOM)is perpendicular to the steel plate, there will be no force at all. however, the DOM will not be straight, particlularly with the present of steel, the magnetic flux will be bent to pass thought the steel plate and back to the the other end of magnet since steel is the easier pass.

### RE: Magnetic lateral force?

From a application view, there is a "drag" force as a result of the cooeficients of friction between the magnet and the load. A rule of thumb is the latteral force is about 25% of the vertical force. This can vary considerably depending on the contact surface conditions, i.e. smooth, rough, oily, etc...

### RE: Magnetic lateral force?

sorry, typing not so good. Should be "coefficient" of friction.

### RE: Magnetic lateral force?

(OP)
So it seems that the lateral force is indeed weaker, a common fact we can agree upon that.
I assume the coefficient of friction could possibly drop significant when a powerful lubricant is added. So the total lateral force decreases.

### RE: Magnetic lateral force?

(OP)
Ow, no no no... I'm creating a system that has to do with magnets.
I'm building a tool that slides off magnets instead of pulling them apart, since I have a HUGE collection of magnets and electomagnetic applications.
s

### RE: Magnetic lateral force?

Couldn't you have led with that tiny morsel of information? This is a completely different scenario than what you implied with your initial post. Now, the "lateral" force is not only irrelevant, it's nonexistent, since the force you are operating against is actually friction driven by the magnetic pull force against the surface, so the force is a function of both the strength of the magnet, and the surface friction/roughness

TTFN
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### RE: Magnetic lateral force?

(OP)
By smoothing out the surfaces or adding ultra-lubricants, I'm essentially decreasing the force correct?
Also, I believe there is a lateral magnetic force but possibly half than initial pull force

"You can feel a lateral magnetic force when two magnets are offset from one another. The graph at right shows an estimate of the lateral magnetic forces between two magnets. The lateral magnetic forces are shown in the dark blue, dashed line. The solid blue line is the sum of the magnetic and friction forces that act in the lateral (x) direction.

While exact answers depend on a lot of factors, we usually figure the force required to shear a magnet sideways off another magnet will be less than the listed Pull Force, Case 1, perhaps about half of that value.
"

Source.

I'm pretty sure that in a general sense,sliding off a magnet off a electromagnet/iron plate/etc... Requires less force than pulling it of, just wanted to be sure.
Thank you all for everything!

### RE: Magnetic lateral force?

(OP)
Sorry but, I didn't get your point:"Note also that there is a big difference between removing from a nonmagnet and removing from a magnet."

Since sliding a magnet from any magnetic surface is less, I think a smooth ultra=lubricated surface is easer than a rough surface,because there is a gap with a rough surface... Could cause an issue.
Also having a strong holding position would make even more easier to slide a magnet off.

Very interesting.

### RE: Magnetic lateral force?

(OP)
@IRstuff

There is a lateral magnetic force when the magnet is on the edge a other magnet/ferromagnet's surface.
Its an attraction force I assume, but still... A weak force in-comparison to the magnetic pull force perpendicular to the surface.
My only explanation is that the magnetic field would prefer the surface instead of air, because it's an easier path.
However, I noticed something that is strange, by increasing more downward force on the magnet acting on the surface, the same direction as the pull force of attraction, it seems that this force on the edge decrease, although the coefficient of friction does, but that's expected... Just wanted to share that piece of info.

### RE: Magnetic lateral force?

(OP)
Indeed they are the same force. However, they are not of the same magnitude.
The magnetic force is strongest when acting perpendicular to a surface... Sliding it, would have generated a weaker force at the edges.

(OP)
@IRstuff

### RE: Magnetic lateral force?

The "force" is a distributed vector field; it's like you're trying to say that your arm is shorter in a different direction, but, it's only because your arm is a 3-dimensional object that is distributed in space and it's all the same arm.

TTFN
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