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False
permanent magnets can but electromagnets need a running current A+
Wiki User
∙ 11y ago
Wiki User
∙ 11y agoAlnico is the usual metal used in making permanent magnets. The material should metal and can be polarized.
Wiki User
∙ 6y agoWe generally refer to this as a permanent magnet.
Wiki User
∙ 14y agoPermeable ones.
Wiki User
∙ 12y agoferromagnetic
Wiki User
∙ 6y agoThey are permanent magnets.
Wiki User
∙ 6y agoIron
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Does a greenhouse retain or release heat?
Compared to the external environment, a greenhouse will retain heat.
Does saltwater prove to retain heat the best or freshwater?
Answer: Pure water has the best capacity for heat of any material known to man, so any impurity must reduce its ability.
Can a magnet be broken?
Not exactly. All pieces of the magnet retain their ferrous properties, but if they were (for example) dropped, then the shock of the fall could potentially make them lose a bit of magnetism. Extreme temperature changes and high power electric discharges could also decrease the power of the magnet.
What does retain mean in science?
to hold onto a characteristic through time
Which is the best reading method to use when you are studying a text and trying to make sense of and retain the information?
scanning
What is magnetization of iron?
the process of converting iron to a permanent magnet is called magnetization. As iron is a ferro magnetic material it is magnetized by applying strong magnetic field across it , this makes the alignment of all the magnetic dipoles present in iron in the same direction .Even after the external magnetic field is removed they retain their arrangement , thus it becomes a permanent magnet
What is the significance of hysteresis?
Hysteresis is the delay between an observed outcome and the quantity of change applied.When a ferromagnetic material is magnetized in one direction, it will not relax back to zero magnetization when the imposed magnetizing field is removed. It must be driven back to zero by a field in the opposite direction. If an alternating magnetic field is applied to the material, its magnetization will trace out a loop called ahysteresis loop. The lack of retraceability of the magnetization curve is the property called hysteresis and it is related to the existence of magnetic domains in the material. Once the magnetic domains are reoriented, it takes some energy to turn them back again. This property of ferrromagnetic materials is useful as a magnetic "memory". Some compositions of ferromagnetic materials will retain an imposed magnetization indefinitely and are useful as "permanent magnets". The magnetic memory aspects of iron and chromium oxides make them useful in audiotape recording and for the magnetic storage of data on computer disks.Variations in Hysteresis CurvesThere is considerable variation in the hysteresis of different magnetic materials.
What magnets are made from materials which retain their magnetic properties for a long time?
Permanent magnets.
What kind magnets are made from materials which retain their magnetic properties for a long time?
Permanent magnets.
What is it in magnets that causes it to attract metal?
Magnets can retain a permanent magnetic field. All atoms have a magnetic field which are randomly arranged in the object. Magnets and ferrous metals can retain or temporarily align the atomic fields, thus they are magnetic.
Why is a electromagnet not a permanent magnet?
An electromagnet only retains major magnetic properties when a current is being run through it.AnswerWhether a material makes a permanent or temporary magnet depends on the nature of the ferromagnetic material involved. For example a coil with a steel core will retain much of its magnetic flux density when the current is switched off, whereas a coil with an iron core will lose most of its magnetic flux density when the current is switched off.
Is rhenium magnetic?
Rhenium is paramagnetic. Paramagnetic materials have a small, positive susceptibility to magnetic fields. These materials are slightly attracted by a magnetic field and the material does not retain the magnetic properties when the external field is removed.
Does the magnetic memory of rock on the ocean floor change over time?
Yes. The ability of a material to retain magnetism after the magnetizing force is removed is magnetic memory.
What is the difference between hard and soft material?
Materials which retain their magnetism and are difficult to demagnetize are called hard magnetic materials. These materials retain their magnetism even after the removal of the applied magnetic field. Hence these materials are used for making permanent magnets. In permanent magnets the movement of the domain wall is prevented. They are prepared by heating the magnetic materials to the required temperature and then quenching them. Impurities increase the strength of hard magnetic materials. Soft magnetic materials are easy to magnetize and demagnetize. These materials are used for making temporary magnets. The domain wall movement is easy. Hence they are easy to magnetize. By annealing the cold worked material, the dislocation density is reduced and the domain wall movement is made easier. Soft magnetic materials should not possess any void and its structure should be homogeneous so that the materials are not affected by impurities.
Why is it unlikely that earths core is a permanent magnet?
An electromagnet only retains major magnetic properties when a current is being run through it.AnswerWhether a material makes a permanent or temporary magnet depends on the nature of the ferromagnetic material involved. For example a coil with a steel core will retain much of its magnetic flux density when the current is switched off, whereas a coil with an iron core will lose most of its magnetic flux density when the current is switched off.
Why Is earth not a permanent magnet?
The simplest evidence that the Earth is not a permanent magnet is given by the fact of the polar wander. But more fundamentally, the interior of the Earth is far too hot for a magnet to retain its field. Pierre Curie worked on many things, and the loss of magnetism at elevated temperatures was one of his discoveries, and is known as the Curie point for a magnetic material. Importantly, the material cannot contain a magnetic field above this point. Thus a transformer will lose its abilities above the Curie point of the (iron) laminations inside.
What is the difference between hard and soft magnetic materials?
Materials which retain their magnetism and are difficult to demagnetize are called hard magnetic materials. These materials retain their magnetism even after the removal of the applied magnetic field. Hence these materials are used for making permanent magnets. In permanent magnets the movement of the domain wall is prevented. They are prepared by heating the magnetic materials to the required temperature and then quenching them. Impurities increase the strength of hard magnetic materials. Soft magnetic materials are easy to magnetize and demagnetize. These materials are used for making temporary magnets. The domain wall movement is easy. Hence they are easy to magnetize. By annealing the cold worked material, the dislocation density is reduced and the domain wall movement is made easier. Soft magnetic materials should not possess any void and its structure should be homogeneous so that the materials are not affected by impurities.
