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The transfer of heat within a material?
You think to thermal conduction.
What is bloch wall energy?
180o domain wall between two domains is known as Bloch wall. The Bloch wall energy is competition between exchange energy and anisotropy energy within the interface of two domains. The exchange energy in a ferromagnetic material is a minimum only when adjacent spins are parallel. While anisotropy energy will be minimum when the spins remain parallel to the easy axis. Bloch wall energy will be minimum of exchange energy and anisotropy energy Mathematically, the Bloch wall energy for an uniaxial anisotropic material will be (sigma)exch+(sigma)anis=(JS2 pi2)/Na2+KuNa where J is exchange stiffness, N is number of atoms within the wall, a is distance between two adjacent atoms, Ku is the uniaxial anisotropy constant the minimum of this energy terms will be (sigma)dw~2pi(AKu)1/2 where A is the exchange stiffness constant. it is the energy of the Bloch wall in uniaxial ferromagnetic material. (read more in Cullity's Book)
What is the effect of variable area to the magnetic flux within the solenoid at constant number of windings and current?
area is equal to the magnetic flux, therefore it is equal.
How can electrons move within a solid?
Unless at absolute zero, they are constantly in motion in all materials. Presisely what motion depends on the material and the conditions that the material is subject to.
Why do conductors conduct electricity?
Conductors have a structure wherein a number of electrons are unbound within it. These electrons are said to be "free electrons" and they are "wandering" within the material. As the electrons are unbound, they are free to support conduction when an voltage is applied, and they will do so will little resistance. The idea of the free electrons is what makes a conductor an conductor, and this is why conductors will support current flow without a lot of resistance. Another way to look at the issue is to compare electron energy levels. Free electrons have high kinetic energies, and they are not "bound" within the material. When we look at the energy levels that electrons occupy in a conductor, and then compare that to the energy levels electrons would have to be in to support current flow (which is the conduction band), there is some overlap. When the conduction band of a material is low enough, it might overlap the Fermi energy levels of some of the electrons within the material (those free electrons). When this happens, the material will then conduct electricity easily.
Is An electromagnet is a solenoid with a piece of ferromagnetic material within it?
True
What material can be used to make an electromagnet?
The magnetic field in an electromagnet is actually produced by the coil of wires with a current running through it. However certain materials, termed 'ferromagnetic' materials concentrate the magnetic flux when a rod of the material is placed within the coil (termed the 'magnetic core'). The most common of materials used for this have been iron based.
Can you magnetize a bit of metal that is not a magnetic type of metal?
Generally, no you can't. A ferromagnetic material has what are called magnetic domains within it. These domains are effectively "tiny magnets" and are randomly arranged when they are in non-magnetized ferromagnetic metals. We can align them and make the material magnetic with the right equipment. A bit of metal that is not ferromagnetic has to domains to realign, so it can't be magnetized.
What happens when the domains of a ferromagnetic material are oriented randomly?
Within the domain the magnetic field can be powerful, but bulk samples of the material will often be unmagnetized since the many domains are randomly oriented with respect to each other.
How do electromagnet work?
If a wire is wrapped around a ferromagnetic material (those which are attracted by a magnet) and a current is flown through the wire, the material behaves like a magnet. This phenomenon is known as electromagnetism. The electromagnet can attract other ferromagnetic material just like any magnet. Usually a soft iron-core is used for good results. By such a phenomenon you get a temporary magnet whose magnetic property can be switched on or of by a switch! You can try this at home by wrapping a wire around an iron-nail and using a battery for current.Hope this helps:)
What rotates within an electric motor?
an electromagnet
The effect of temperature on magnetic strength?
An electric current flowing in a straight wire creates a magnetic field around the wire. Notice the "right hand" rule for determining the orientation: when the thumb of the right hand is pointing in the direction of the current, the fingers of the right hand curl in the direction of the magnetic field. we can see the effect of this magnetic field by bringing the wire close to the needle of a magnetic compass when the current is flowing. we can even make an electric current detector based on this principleA current flowing through a coil of wire (the coil is also called a solenoid) creates a stronger magnetic field than the same current flowing through a straight wire. The magnetic field is strongest at the center of the coil. Each loop in the coil contributes additional strength to the magnetic field. The more loops, the stronger the field.The magnetic field of a solenoid can be increased even further by placing a bar or rod of ferromagnetic material within the coil (diamagnetic and paramagnetic materials will also work, but will not retain a magnetic field when the current is turned off). The magnetic field from the coil strongly aligns all of the magnetic domains in the ferromagnetic material, creating a much stronger magnetic field than either the coil or the ferromagnetic material would have alone.Permanent magnets are made from ferromagnetic materials. Ferromagnetic materials can "remember" their magnetic history. If a ferromagnetic material is exposed to a strong magnetic field, the magnetic domains within the material will retain at least some of the alignment induced by the external magnetic field.When the temperature of a material is increased, what is happening on the atomic scale is an increase in the random motion of the atoms of which the material is made. There is random motion of atoms could affect the alignment of magnetic domains, so that increasing the temperature of a magnet would tend to decrease its strength. If we placed in oscillator there is change in voltage,current, frequencies by these variables we can find temperature of the substances
Coils of wire wrapped around a ferromagnetic core make up a motor's?
Coils of wire wrapped around a ferromagnetic core make up a motor's armature. It carries an electrical current and rotates within a magnetic field.
What material contained within the nucleus?
Chromatin material is contained within the nucleus.
How is a electromagnet different then a permanent magnet?
I will attempt to answer this but my expertise on magnetics is low, so improvements are welcomed if necessary. The main difference is that an electromagnet requires a current to be magnetic, the potential difference means electrons flow to one end of the system (toward the anode) and so you polarise the material. Meaning one end is now positive, the other negative.At least, generally speaking.However if you took the current away, the material would reorder itself atom-wise and lose it's magnetic properties.A permanent magnet as we commonly know them exhibit ferromagnetic properties, meaning the atoms do not reorder so randomly in the absence of a current. They like being that way and so will stay that way permanently (within reason).Hence you can make some things magnetic by rubbing a magnet against then, reorganising their structure. If the material allows it to stay that way, you get a magnetic paperclip and so forth.
What is the material within a cell like?
The material within a cell, known as cytoplasm, is gelatinous.
What function digests material within a cell?
A lysosome digests material within a cell.
