what is meant by MAGNETIC MOMENT?

Answer 1

There are not "magnetic charges", or "magnetic monopoles". The simplest magnetic object possible is the "magnetic dipole".

If you think about electric charges, it is easy to understand an electric dipole, and then extend the concept to magnetism. An electric dipole is composed of two opposite charges, located very closed from each other. The electric field generated by the arrange are closed lines, starting on the positive charge and ending on the negative. The important magnitud is not the charge of each particle, or the distance between them, but the product of this two magnitudes: this is the electric moment of the dipole (in fact, the electric moment is a vector, pointing in the direction from the negative to the positive charge).

Now, think about the magnetic dipole. There are no charges, but the (magnetic) field is similar to the (electric) field generated by the electric dipole. The "strenght" of the dipole is measured by its magnetic moment, a vector.

Magnetic dipoles are not attracted (nor repealed) by uniform magnetic fields. In fact, they suffer a torque trying to align them with the field. But they suffer a net force when are placed into a non-uniform magnetic field, proporcional to the gradient of the field.

Answer 2

i don't know the exact things about it. but it's the current forces magnets are exurting on each other a a give time, look on wikipedia

Answer 3

\int J \cross R dv

Answer 4

i thot it was magic moment...well maybe you two are attracted to one another...or whoever we are talking about...