How can I determine the force of a magnet, and how far the field extends? Does the force decrease with distance?
2007-03-16 10:37:30 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Physics
Theoretically, only for simple shaped highly symmetrical magnets it is possible to estimate the magnetic field in relation to the magnet's axes. Examle are a solenoid coil or a Helmholtz Pair.
In real life you'd need a Hall probe to figure out the magnetic field profile in each point in space near your magnet.
2007-03-16 11:49:14 · answer #1 · answered by Snowflake 7 · 0⤊ 0⤋
In theory, the force of a magnetic field on a particle is given with the equation
F = qvBsin(theta), where q is the charge of the particle, v is its velocity, B is the strength of the magnetic field, and theta is the angle between the magnetic field and the direction of the particle.
So, if you wanted to find the strength of the magnetic field, you could determine it by calculating the other variables, though I imagine it would be somewhat difficult.
The strength of the magnetic field (B) will, as you said, get weaker as distance increases, following the inverse-square law - that is, it decreases relative to the square of the distance (so it decreases faster)
2007-03-16 18:27:09 · answer #2 · answered by cluekoo 4 · 0⤊ 0⤋
Magnets are created naturally in some cases over time, but can be easily RE-CREATED simply by charging the poles of a conductive element (steel works well) with a barrage of negative or positive ions.
This can be acheived by looping a strong electrical conducter in a circular form and charging it up with electricity, then passing the steel through the charged circle.
The magnet can be discharged by passing the charged stell back through the circle backwards.
This is called magnetic induction
You can work out the force of the magnet or the depth of it's field, by determining the level of induction (the amount of electricity passing through the electrified coil and then adding a factor depending on the purity and conductivity of the steel being passed through it. (ie accountign for things like eddie currents and other losses).
This pragmatic process is also used to make measuring devices which determine how strong naturally occuring magnets are.
BUT truth be told it can only ever be a guestimate with varying degree of accuracy for extremes.
2007-03-16 19:11:55 · answer #3 · answered by Anonymous · 0⤊ 0⤋
The force of attraction is inverse squared proportion to the distance.
2007-03-16 18:15:32 · answer #4 · answered by Oz 4 · 0⤊ 0⤋