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It can be more easily explained if one work backwards from the equation:
where
B is the magnitude of flux density in teslas
F is the force in newtons experienced by a wire carrying
So, one can see for a magnetic flux density to equal 1 tesla, a force of 1 newton must act on a wire of length 1 metre carrying 1 ampere of current.
1 Newton is a lot of force, and is not easily accomplished. To put it in perspective: the most powerful superconductingSuperconductivity is a phenomenon occurring in certain materials at low temperatures, characterised by the complete absence of electrical resistance and the damping of the interior magnetic field (the Meissner effect. In conventional superconductors, supe electromagnetAn electromagnet is a type of magnet in which the magnetic field is induced by a flow of electric current. The magnetic field disappears when the current ceases. right-hand rule. The simplest type of electromagnet is a coil of wire. A coil forming the shas in the world have flux densities of 'only' 20T.
This is true obviously for both electromagnets and natural magnets, but a magnetic field can only act on moving charge - hence the current, I, in the equation.
Indeed, the equation can be played around with to incorporate moving single charges, ie protons, electrons, and so on via
where
Q is 1 coulombThe coulomb symbol C, is the SI unit of electric charge, and is defined in terms of the ampere: 1 coulomb is the amount of electric charge carried by a current of 1 ampere flowing for 1 second. It is also about 6. 241506×1018 times the charge of an electr of charge
v is the velocity of that charge in metre per secondMetre per second ( U. spelling: meter per second is an SI derived unit of both speed ( scalar) and velocity ( vector), defined by distance in metres divided by time in seconds. The symbol is m/s or equivalently, m s-1 . Some examples of speeds in m/s: Con
FlemingSir John Ambrose Fleming sometimes also listed as Ambrose J. Fleming November 29, 1848 April 18, 1945) was a British electrical engineer and physicist. Early years Fleming was born in Lancaster and educated at University College School, London and UCL.'s left hand rule can be used to determine the direction of motion/current/polarity from any two of those, as seen in the example.| SI magnetism units [ }|action=edit}} Edit }] | |||
|---|---|---|---|
| SI Derived units | |||
| Name | Symbol | Quantity | Notes |
| weber | Wb | Magnetic flux | |
| tesla | T | Magnetic flux density | |
| ampere / metre | A / m | magnetic induction | |
| ampere-turns / Weber | A / Wb | Reluctance | |
| Henry per metre | H / m | Permeability | |
| Magnetic susceptibility | |||