Dear Rakibul
The term "emu" is short for "electromagnetic unit". This is not a unit in the conventional sense.
It is sometimes used as:
Magnetic moment: 1 emu = 1 erg/G (where G=Gauss) ==> 10-3 A m2 or 10-3 J/T(T = Tesla) .
Mass magnetization: M = emu/g
Magnetization per volume: emu/ cm3
Magnetic field strength H : Oe=Oersted
Best regards, Carlos
Hello Rakibul,
H is the magnetic field and M the magnetisation.
In SI-units (SI - system international) both quantities have the unit A/m. In older literature, the cgs system is used. Therefrom derived magnetic units are summarized in the system of "electromagnetic units = emu".
Herein are 1 emu = 1 erg / 1 Gauss (erg - energy unit, Gauss corresponds to Tesla in SI)
In the electromagnetic system H is measured in
Oerstedt (SI :A/m) and
M is measured in 1 emu/cm3
Obviously, the unit "g" in your text is not gramm but "G" like Gauss.
With Regard
R. Mitdank
It represents how magnetic hard is the material in analysis.The larger the product, the more magnetic hardness the material has, and suited to an application that requires more magnetic energy. In terms of unit in the international system (SI), it is possible convert emu to Am2 that is J/T (ieeemagnetics), and so m(emu) x H(T) = J/T x T, that is energy (J).
Hello Rakibul,
“emu” is known as “electromagnetic unit”.
Mass magnetization: M = emu/g (electromagnetic unit per each gram of the material under test -- Magnetization per each gram).
Magnetization per volume: emu/cm3 (Some materials are not in their solid form. For example, some material that are under test are in liquid form. In that case, emu/cm3 , is electromagnetic unit (magnetization) per each centimeter cube of the material under test).
Magnetic field strength H : Oe=Oersted
Please note that in order to correctly compare the magnetization of any material to another material (APPLE to APPLE comparison), the scientific community report the magnetization of the material under test as emu/g or emu/cm3 (or other similar entities).
You also asked what (emu-Oe/g) indicates. This is the magnetization of the material, per 1 gram of that material’s mass, per 1 unit of applied magnetic field (in Oersted).
Good luck.
I would like to add some more information about the terminology used, as well as give my answer, which lies somewhat in a different plane and, as it seems to me, corresponds more to the question asked. First, let's clarify the notation for magnetization. In the process of measurements, it is more convenient to operate with the concept of the magnetic moment of the mass unit, or specific magnetization Mm, or specific intensity of magnetization. On the other hand, in electrodynamics, the concept of magnetization is more often used, defined as magnetic moment per volume unit, or volume density of magnetic moment Mv. There is an obvious relationship between them: Mm*d = Mv, where d is the density of the material. The scalar product Mv*H corresponds to the energy stored per volume unit, i.e. erg/cm3, and Mm*H= Mv*H/d corresponds to the energy attributed to the mass unit, erg/g.
Dear Rakibul,
Please pay attention to the fact that my previous post corrects statements by Amir Aslani and Miguel Angel Cobos Fernández that "You also asked what (emu-oe/g) indicates. This is the magnetization of the material, per 1 gram of that material's mass, per 1 unit of applied magnetic field (in Oersted)" and that "...m(emu) x H(T) = J/T x T ... is energy", contradicting each other by themselves.
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