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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.
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.
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.
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:)
an electromagnet
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 armature. It carries an electrical current and rotates within a magnetic field.
Chromatin material is contained within the nucleus.
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.
The material within a cell, known as cytoplasm, is gelatinous.
A lysosome digests material within a cell.