These impurities help tame the magnetic fields caused by current inside the wire, increasing its capacity.
When something that conducts electricity sweeps through a magnetic field, a current starts to flow through it (this is the basis of a dynamo).
When Cluster II passes through these so-called polar cusps, instruments on board each of its satellites will measure the magnetic field, electrical current and number of charged particles within the tetrahedron.
The coil is suspended in an external magnetic field and the current running through it adjusted so that the attraction between the two magnets balances the gravitational force on the suspended mass.
Creating a magnetic field using electricity is easy: an electric current flowing in a wire generates a magnetic field around that wire.
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Such a thin layer alters the current flow in a way that reduces the current's susceptibility to magnetic interference.
The radiation belt, which contains "two concentric rings of charged particles trapped by Earth's magnetic fields" doesn't affect current astronauts going to and from space because they are moving too fast to be hit by the radiation.
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Dr Benford reckons some of them could have built up an electric current as they moved through the strong magnetic field that pervades the centre of the galaxy.
However, this current itself twists around and around as it flows through the magnetic field, the way a torrent of water twists up a fire-fighter's hosepipe.
As the train's magnets pass over a frame, they induce an electric current in it and this, in turn, generates a magnetic field which repels the magnet that started the whole process and thus levitates the train.
And when a magnetic field line vibrates, he says, it makes an electric field which excites current in wires.
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MRAM, a next-generation memory based on magnetic materials, has emerged as an alternative to SRAM because it is non-volatile, cutting leak current during standby status.
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