# Tesla magnetic field holding force and horsepower to remove magnet

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1. Jul 22, 2015

### Ankhen

Hi. Is it posible to make an equation to solve this:
How many horsepower does it takes to remove a magnet with the force of 1 tesla, from a piece of metal. ?

The surface of the magnet and the surface of metal is the same size.

I gues the angel of witch the magnet is being pulled affects the equation, and also the distance between the magnet and the surface of the metal, if there not touch each other
There must be and equation for this, but I cant solve it. Anyone?
Regards Morten

2. Jul 22, 2015

### Staff: Mentor

Your units are wrong and that obscures your question. A tesla is a unit of magnetic flux density, not a force. Horsepower is energy per unit time, not a force. Ask again with correct units.

Also remember that all metals are not equal.

3. Jul 23, 2015

### Ankhen

Hi anorlunda. Then maybe you could help me out
I know the units are wrong. Thats why I have problems with it.
What im asking is: How do I calculate the force im using to pull a magnet down/away from the
refrigerator

How much force does it takes to remove a magnet with the strength X, from a metal surface.
And again the angel, surface-size, sort of metal and distance between magnet and metal must have influence
Regards Morten

4. Jul 23, 2015

### Staff: Mentor

The basic formulas can be found on Wikipedia here. But be warned, the equations are difficult to understand and to use. More important, to use them you need to know important parameters such as the flux density of the magnet and the metallic alloy composition of your refrigerator. Since you probably have no way to know those parameters, you can't apply the formulas.

I suggest that instead of calculating the force for your refrigerator magnet, that you try to measure it experimentally.

5. Jul 24, 2015

### Ankhen

Hi again
Im trying to find a equation not just the answer to me examble above
it seems like you know a thing or two about this topic. Is it possible to find you on facebook, so we can write together in real time instead of waithing for answers all the time ?
Regards morten

6. Jul 24, 2015

### Drakkith

Staff Emeritus
The unfortunate fact is that you're unlikely to be able to use the equations even if you find them. Do you know any calculus, specifically integration?

7. Jul 24, 2015

### Ankhen

Hi Drakkith.
1)why
2)no

8. Jul 24, 2015

### Drakkith

Staff Emeritus
Because when I look up all the different equations involving magnets, I see a lot of stuff that appears to use integration, gradiants, vectors, and other complicated math. If you haven't been formally educated in calculus and further math, I don't see how you can use them.

9. Jul 24, 2015

### Ankhen

I see what you mean. I havent been educated in those things, but when I look it up in wiki or other sites, things like Gauss, Lorenzt and Faradays laws, I understand the math. But Im not that good in english, so im affaid that i miss somethings in the translation.

10. Jul 24, 2015

### Drakkith

Staff Emeritus
If you don't understand integration, differentials, and gradiants, then there's no way you understand the equations.

Here's Gauss's law:

In order to use it, you need to convert it into an integral:

Now, do you know what any of that means? Can you actually use it to solve a problem?

Last edited by a moderator: Apr 16, 2017