I need make normal working electromagnet for my daughter school project. I am electric and not like 100 turn coil, current 100A - keep 1V5 Duracell with gloves. But cannot find simple formulas for calculations for electromagnet. I have
10mm ferrum centre
3V school battery maybe max current 0.5A
Item for raise 2g
temperature 20C
Have you been able to figure out the force of your electromagnet from equations in this thread? There are also some equations at
Electromagnet - Wikipedia, the free encyclopedia. I didn’t look specifically at what type(s) of electromagnets these equations are for. However, the page does mention that the use of ferromagnetic materials such as ferrum – which I have just learned means iron, in electromagnets results in a much stronger magnetic field. So, this would be an important consideration when looking for a formula. I can’t help you with the current of your battery. According to the formula at
Electric current - Wikipedia, the free encyclopedia, the current of the circuit that you hook your battery up to increases as the voltage increases, and decreases as the resistance increases. I don’t really understand this, because it would seem to follow that the current would be infinite if the resistance is zero – which doesn’t make sense to me. There is a chart of the capacity of batteries at **broken link removed**) that includes information about the amps of batteries, the energy of batteries, and other technical terms that I would have to study and review. I don’t know if you should be concerned if temperature is not included in the equation that you find. I calculated the temperature of your conditions to be about 68 degrees Fahrenheit. This seems to me to be about room temperature, which I imagine is what most formulas are made for unless otherwise specified. It may be that the optimal operating conditions for electromagnets are much different from room temperature. Perhaps this optimal temperature is as cold as possible without too many crystals forming on the electromagnet from the atmosphere. However, I don’t know if these crystals would block or enhance the desired magnetic field. This information may be helpful in describing the magnetic field produced by your electromagnet.
Do you know of the magnetic properties of the item? I think that it may be that the magnetic field of the item interacts with the magnetic field of the electromagnet to produce a force. I don’t know how to calculate the height that the item will be raised based on the upward force produced by these interacting magnetic fields and the downward force of gravity. However, I imaging that the surface of the shapes – such as whether these surfaces have round or concave shapes – would be important. You question seems uniquely different from the content of this thread to me, and if it hasn’t already been asked in another thread, you might consider making a new thread. I think that you might have to figure out the magnetic properties of your item and the way that magnetic properties of two items suspended in air interact to produce a force. I looked briefly for a database of the magnetic field of materials without success – though I imagine such databases are readily available. There is some information at
Magnetic field - Wikipedia, the free encyclopedia about fields. However, I don’t know if you can just add the strength of the fields together to find the overall field - because I don’t think that the strength of these two fields can be considered independently from the height of the item. I imagine that all three variables – representing the fields and distance between the electromagnet and the item, are interrelated.
You could start off by calculating the downward force of gravity on your item. The equation for this is force, F = ma, can be found at
Force - Wikipedia, the free encyclopedia. m = mass = kilograms = 1000 grams. Your item is about .002 grams. a = gravity = about 9.8 m/s2.