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The difference between an electromagnet and a bar magnet is that the bar (steel) magnet is always turned on, therefore always magnetic. The electromagnet is a magnet that is powerd by a battery so you can turn it on and off.
Wiki User
∙ 12y ago
Wiki User
∙ 15y agoModern theories of magnetism maintain that a magnetic field is produced by an electric charge in motion, and thus it is theorized that the magnetic field of a so-called "permanent" magnets such as lodestone is the result of electrons within the atoms of iron spinning uniformly in the same direction.
Wiki User
∙ 11y agoWiki User
∙ 8y agoA permanent magnet (e.g. steel) is a material which retains its magnetism once any external magnetizing force has been removed. For example, when the current passing though a coil wound around that material is switched off. Permanent magnets are used in certain measuring instruments, such as moving-coil instruments, fridge magnets, etc.
A temporary magnet (e.g. iron) is a material which retains its magnetism providing any external magnetizing force continues to be applied. For example, when the current passing though a coil wound around that material flows, it will continue to act as a magnet, but once the current is turned off it will lose that magnetism (or most of it!). Temporary magnets are used to manufacture relays, transformer cores, etc.
Wiki User
∙ 6y agoA permanent magnet is always magnetised (example is a simple bar magnet). An electromagnet is only magnetised while an electrical current is flowing through the coil. Once the electricity is switched off, the electromagnet ceases to be magnetised.
Wiki User
∙ 12y agofor permanent magnet no current is needed to pass through it,where as non permanent magnets like (soft iron) needs current to make it a magnet and after current goes it is no more a magnet.
Wiki User
∙ 15y agoElectromagnets can be turned on and off using an electrical switch, whereas it is much more difficult to destroy a permanent magnet.
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What is the role of permanent magnets in a speaker?
The electromagnet is positioned in a constant magnetic field created by a permanent magnet. These two magnets -- the electromagnet and the permanent magnet -- interact with each other as any two magnets do. The positive end of the electromagnet is attracted to the negative pole of the permanent magnetic field, and the negative pole of the electromagnet is repelled by the permanent magnet's negative pole. When the electromagnet's polar orientation switches, so does the direction of repulsion and attraction. In this way, the alternating current constantly reverses the magnetic forces between the voice coil and the permanent magnet. This pushes the coil back and forth rapidly, like a piston.
Compare an electromagnet and a permanent magnet?
See compare and contrast permanent vs. temporary magnet. Unless, of course, they are truly two different questions.
Why permanent magnet is not used to lift heavy load?
But they are! You can find lifting magnets based on permanent magnets all over in machine shops.
What is a magnet that can be turned on and off called?
Electromagnets have an electric current running through them that enables there conductive power to be strengthened. However, a magnets full conductive power can never be "turned off/on".
What are the three classification of magnets?
Permanent MagnetsPermanent magnets are those we are most familiar with, such as the magnets hanging onto our refrigerator doors. They are permanent in the sense that once they are magnetized, they retain a level of magnetism. As we will see, different types of permanent magnets have different characteristics or properties concerning how easily they can be demagnetized, how strong they can be, how their strength varies with temperature, and so on.Temporary MagnetsTemporary magnets are those which act like a permanent magnet when they are within a strong magnetic field, but lose their magnetism when the magnetic field disappears. Examples would be paperclips and nails and other soft iron items.ElectromagnetsAn electromagnet is a tightly wound helical coil of wire, usually with an iron core, which acts like a permanent magnet when current is flowing in the wire. The strength and polarity of the magnetic field created by the electromagnet are adjustable by changing the magnitude of the current flowing through the wire and by changing the direction of the current flow.
What is the ifference between an electromagnet and a permanent magnet?
Electromagnets and permanent magnets both attract or repel other magnets and attract iron and other substances. An electromagnet is a magnet that is only active when it has a current passing through it; permanent magnets are always active.
What are the advantages and disadvantage's of an electromagnet?
an electromagnet requires electricity and you will have to pay for it. permanent magnets are always on and you can change the strength of it.
Objects that keep their magnetic properties for a long time?
A permanent magnet (in contrast to an electromagnet).
What is the role of permanent magnets in a speaker?
The electromagnet is positioned in a constant magnetic field created by a permanent magnet. These two magnets -- the electromagnet and the permanent magnet -- interact with each other as any two magnets do. The positive end of the electromagnet is attracted to the negative pole of the permanent magnetic field, and the negative pole of the electromagnet is repelled by the permanent magnet's negative pole. When the electromagnet's polar orientation switches, so does the direction of repulsion and attraction. In this way, the alternating current constantly reverses the magnetic forces between the voice coil and the permanent magnet. This pushes the coil back and forth rapidly, like a piston.
Where is the electromagnet in a maglev train?
the electromagnet is in the track then there are permanent magnets on the very bottom of the train on the part that wraps around the track
Can Permanent magnets be turned on and off?
Electromagnet which uses electric current can be turned on and off.
What are the advantages and disadvantages of electromagnetism?
an electromagnet requires electricity and you will have to pay for it. permanent magnets are always on and you can change the strength of it.
Compare an electromagnet and a permanent magnet?
See compare and contrast permanent vs. temporary magnet. Unless, of course, they are truly two different questions.
Are electromagnets used in generatorsto transform mechanical energy into electrical energy?
This requires magnets in general. It need not be an electromagnet; sometimes electromagnets are used, sometimes permanent magnets.
What are the eleven types of magnets?
There are two fundamental types of magnets, permanent and electromagnet. Both of these may be presented in numerous forms, and there seems no merit in considering any particular eleven.
Why electromagnets over permanent magnets for a large dc machine?
The flux density of an electromagnet can be easily controlled. It's also easy and cheap to produce a large flux density with an electromagnet which is necessary for such large dc motors. Permanent magnets are generally expensive. For such a large motor,a very large permanent magnet will be needed for that motor which will not be ideal.AnswerElectromagnets are more powerful than temporary magnets, and -as pointed out above- their flux density can be controlled.
What are the simalarities and difforences between an electro magnet and a permanent magnet?
Similar Each produces a magnetic field Each has a north and a south pole Different You can turn an electromagnet on and off. Permanent magnets are always "on". They are made from different materials Electromagnets require power. Permanent magnets don't. You can easily vary the strength of an electromagnet, but not a permanent magnet Some permanent magnets occur naturally and have been around for longer than humans have been. Electromagnets were not invented until the 1800's Electromagnets are capable of producing more intense magnetic fields than permanent magnets The names of some permanent magnets are more fun to say: neodymium-iron-boron Just thought I'd toss in that last one
