michael faraday discovered that moving electricity creates a magnetic field.
michael faraday discovered that moving electricity creates a magnetic field.
who discovered that moving electricity creates a magnetic field?
michael faraday
"voyager"s observations revealed that uranus' magnetic field is peculiar, both because it does not originate from its geometric centre, and because it is tilted at 59° from the axis of rotation. in fact the magnetic dipole is shifted from uranus' centre towards the south rotational pole by as much as one third of the planetary radius. this unusual geometry results in a highly asymmetric magnetosphere, where the magnetic field strength on the surface in the southern hemisphere can be as low as 0.1 gauss (10 µt), whereas in the northern hemisphere it can be as high as 1.1 gauss (110 µt). the average field at the surface is 0.23 gauss (23 µt). studies of "voyager 2" data in 2017 suggest that this asymmetry causes uranus' magnetosphere to connect with the solar wind once a uranian day, opening the planet to the sun's particles. in comparison, the magnetic field of earth is roughly as strong at either pole, and its "magnetic equator" is roughly parallel with its geographical equator. the dipole moment of uranus is 50 times that of earth. neptune has a similarly displaced and tilted magnetic field, suggesting that this may be a common feature of ice giants. one hypothesis is that, unlike the magnetic fields of the terrestrial and gas giants, which are generated within their cores, the ice giants' magnetic fields are generated by motion at relatively shallow depths, for instance, in the water–ammonia ocean. another possible explanation for the magnetosphere's alignment is that there are oceans of liquid diamond in uranus' interior that would deter the magnetic field.
uranus
if an external magnetic field is applied horizontally, so that it crosses the flow of electrons (in the wire conductor, or in the electron beam), the two magnetic fields will interact. michael faraday introduced a visual analogy for this, in the form of imaginary magnetic lines of force: those in the conductor form concentric circles round the conductor; those in the externally applied magnetic field run in parallel lines. if those on one side of the conductor are running (from the north to south magnetic pole) in the opposite direction to those surrounding the conductor, they will be deflected so that they pass on the other side the conductor (because magnetic lines of force cannot cross or run contrary to each other). consequently, there will be a large number of magnetic field lines in a small space on that side of the conductor, and a dearth of them on the original side of the conductor. since the magnetic field lines of force are no longer straight lines, but curved to run around the electrical conductor, they are under tension (like stretched elastic bands), with energy bound up in the magnetic field. since this energetic field is now mostly unopposed, its build-up or expulsion in one direction creates — in a manner analogous to newton's third law of motion — a force in the opposite direction. since there is only one moveable object in this system (the electrical conductor) for this force to work upon, the net effect is a physical force working to expel the electrical conductor out of the externally applied magnetic field in the direction opposite to that which the magnetic flux is being redirected to — in this case (motors), if the conductor is carrying conventional current "upwards", and the external magnetic field is moving "away from" the viewer, the physical force will work to push the conductor to the left. this is the reason for torque in an electric motor. (the electric motor is then constructed so that the expulsion of the conductor out of the magnetic field causes it be placed inside the next magnetic field, and for this switching to be continued indefinitely.)
fleming's left-hand rule for motors