This is possible to be demonstrated when analysing the following equation:
Power = Voltage Current → (P=VI)
This shows that if the current increases, so does the power, subsequently increasing the strength of the electromagnetic field. This means that as the electromagnetic field is stronger, a larger amount of iron filings will be attracted to the magnetised core. I know that magnetic effects are produced by a moving electrical charge (current). This indicates to me that the current will cause the core to have a magnetic field.
To become magnetic in the first place, the electrons in the c-core will have to align themselves. In order to do so, they group together in domains. The main implication of these domains is that there is already a high degree of magnetization in ferromagnetic materials within individual domains, but that in the absence of external magnetic fields those domains are randomly oriented. A modest applied magnetic field can cause a larger degree of alignment of the magnetic moments with the external field, giving a large multiplication of the applied field.
In other words, the majority of these domains are usually only partly aligned, and the strength of the magnetic field around the core will increase as the magnetic domains align. Therefore an electromagnet will keep getting stronger gradually as the magnetic domains become all aligned up
An A.C current would demagnetise the core while a D.C. current would magnetise a core. This is because the D.C. current is direct and therefore all the electrons are arranged in the same order creating a magnetic field. When the current is A.C, the electrons are free to move where they want so there is no magnetic field. When an electromagnet has a current induced in it, it becomes magnetised and the greater the current induced the greater the strength. In addition, if the solenoid receives greater current then the field it generates will be stronger. When I increase the current flowing through the circuit, the magnetic domains are influenced by this current, and they align in the direction of the current. If the current is low, only the domains nearer to outside only will be influenced. When the current gradually increases it reaches the domains present in the inside, therefore increasing the overall strength of the electromagnet. This can be demonstrated with the aid of the experiment which we will describe further on, in more detail. Generally, As the magnetic field around the core becomes stronger, a larger amount of iron fillings will be attracted to the magnetised core. As the current is increased in a wire, the strength of the magnetic field becomes greater and therefore more effective
Eventually though, I predict that the magnetic field around the core will stop getting stronger, (therefore the electromagnet will stop getting stronger). This happens because all the magnetic domains will be aligned up and the electromagnet will have reached its full potential and can be described as “saturated”. This behaviour can be demonstrated graphically: the curve displaying the relationship between the two variables (current, strength of electromagnet) will eventually level off, showing that the amount of iron filings attracted to the core will not grow anymore.