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An electromagnet is made from a coil of wire that acts as a magnet when an electric current passes through it but stops being a magnet when the current stops.
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electromagnet and is
* Electromagnetic clutch: Typically a clutch that is engaged by an electromagnet that is an integral part of the clutch assembly.
An electromagnetic coil ( or simply a " coil ") is formed when a conductor ( usually an insulated solid copper wire ) is wound around a core or form to create an inductor or electromagnet.
An electromagnet is a type of magnet whose magnetism is produced by the flow of electric current.
The rocket is fired when the computer sends direct current through a small electromagnet that opens the poppet valve.
The central spike forms one pole of an electromagnet and is surrounded by an annular space and around that is the other pole of the electromagnet, with a radial magnetic field in between.
The original NASA design proposes a spacecraft containing a can-shaped electromagnet into which a plasma is injected.
Each dot is produced by a tiny metal rod, also called a " wire " or " pin ", which is driven forward by the power of a tiny electromagnet or solenoid, either directly or through small levers ( pawls ).
An electromagnet, in its simplest form, is a wire that has been coiled into one or more loops, known as a solenoid.
For example, PCC trolley brakes include a flat shoe which is clamped to the rail with an electromagnet ; the Murphy brake pinches a rotating drum, and the Ausco Lambert disc brake uses a hollow disc ( two parallel discs with a structural bridge ) with shoes that sit between the disc surfaces and expand laterally.
An electromagnet is a type of magnet in which the magnetic field is produced by the flow of electric current.
To concentrate the magnetic field, in an electromagnet the wire is wound into a coil with many turns of wire lying side by side.
This is called a ferromagnetic-core or iron-core electromagnet.
The main advantage of an electromagnet over a permanent magnet is that the magnetic field can be rapidly manipulated over a wide range by controlling the amount of electric current.
Before the current in the electromagnet is turned on, the domains in the iron core point in random directions, so their tiny magnetic fields cancel each other out, and the iron has no large scale magnetic field.
So the strength of the magnetic field possible from an iron core electromagnet is limited to around 1. 6 to 2 T.
The magnetic field created by an electromagnet is proportional to both the number of turns in the winding, N, and the current in the wire, I, hence this product, NI, in ampere-turns, is given the name magnetomotive force.
electromagnet and made
He found that the discharge caused a fluorescent glow to form on the glass walls of the vacuum tube, and that the glow could be made to shift by applying an electromagnet to the tube, thus creating a magnetic field.
Early measurements were made using the Gouy balance where a sample is hung between the poles of an electromagnet.
A superconducting magnet is an electromagnet made from coils of superconducting wire.
" Callan thought of his creation as a kind of electromagnet ; but what he actually made was a primitive induction transformer.
The most significant idea incorporated in the patent was his plan for inverting the needle telegraph earlier developed by Ampere, Wheatstone and others: instead of making signals by a pivoted magnetic needle under the influence of an electromagnet, he made them by suspending a movable coil between the poles of a fixed magnet.
electromagnet and from
To engage the clutch, an electromagnet attracted the pawl away from the sleeve.
When the clutch was to disengage power was disconnected from the electromagnet and the pawl moved close to the sleeve.
Magnetic fields in the magnetosphere arise from the Earth's internal magnetic field as well as from electric currents that flow in the magnetospheric plasma: the plasma acts as an electromagnet.
Image: Tin_80gauss_1. 6K. jpg | The cylinder has been cooled from 4. 2 K to 1. 6 K. The current in the electromagnet has been kept constant, but the tin became superconducting at about 3 K. Magnetic flux has been expelled from the cylinder ( the Meissner effect ).
With the teeth aligned to electromagnet 1, they will be slightly offset from right electromagnet ( 2 ).
When the gear's teeth are aligned to the first electromagnet, they are slightly offset from the next electromagnet.
So when the next electromagnet is turned on and the first is turned off, the gear rotates slightly to align with the next one, and from there the process is repeated.
Davenport bought an electromagnet from the Crown Point factory and took it apart to see how it worked.
Power is supplied to the electromagnet from some sort of fast discharge storage device, typically a battery or high-capacity high voltage capacitors designed for fast energy discharge.
During braking, the metal wheels are exposed to a magnetic field from an electromagnet, generating eddy currents in the wheels.
Just before an impulse noise ( door slam, electromagnet lock slapback, gunshot, pound of hammer on nail ) one could vocalize ( or cough or hum ) to protect one's hearing from the sound pressure that the impending sound would create.
The system suffers one drawback in that on single track lines, the track equipment will set the AWS system on a train travelling in the opposite direction from that for which the track equipment is intended but not reset it as the electromagnet is encountered before the permanent magnet.
In the external inductor lamps, high frequency energy, from the electronic ballast, is sent through wires, which are wrapped in a coil around a ferrite inductor on the outside of the glass tube, creating a powerful electromagnet called an inductor.
Alternatively, the electromagnet may be arranged to tip the bulb of a small rectifier, just enough to allow mercury from the pool to reach the starting electrode.
# Separate all aluminum from the waste metals with an electromagnet,
The magnetic field of the electromagnet collapses, and the clapper springs away from the bell.
Strowger or crossbar systems, in contrast, use individual electromagnets for operation: the power available from an electromagnet limits the maximum size of the switch element it can move.
electromagnet and coil
Some used a liquid transmitter, some had a metal diaphragm that induced current in an electromagnet wound around a permanent magnet, and some were " dynamic "-their diaphragm vibrated a coil of wire in the field of a permanent magnet or the coil vibrated the diaphragm.
The most common form of loudspeaker uses a paper cone supporting a voice coil electromagnet acting on a permanent magnet, but many other types exist.
The coil of an electromagnet, called a field coil, was energized by current through a second pair of connections to the driver.
When it was desired to produce a dot, a coil ( electromagnet ) wrapped around the pole-piece would neutralize the magnetic field.
A simple electromagnet consisting of a coil of insulated wire wrapped around an iron core.
The coil is shaped such that the armature can be moved in and out of the center, altering the coil's inductance and thereby becoming an electromagnet.
He was the first to coil insulated wire tightly around an iron core in order to make a more powerful electromagnet, improving on William Sturgeon's electromagnet which used loosely coiled uninsulated wire.
He also showed that, when making an electromagnet using just two electrodes attached to a battery, it is best to wind several coils of wire in parallel, but when using a set-up with multiple batteries, there should be only one single long coil.
Where the stator is an electromagnet, the coil which energizes it is known as the field coil or field winding.
In many other applications it is an unwanted contamination, for example a magnetization remaining in an electromagnet after the current in the coil is turned off.
A typical coilgun, as the name implies, consists of a coil of wire, an electromagnet, with a ferromagnetic projectile placed at one of its ends.
The magnetomotive force in an inductor or electromagnet consisting of a coil of wire is given by:
The central controller system vibrated the electromagnet like an audio-speaker voice coil.
The electromagnet ( or " coil ") provides the driving force to close the contacts.
The electromagnet coil draws more current initially, until its inductance increases when the metal core enters the coil.
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