Motion of the Magnetization Vector in a Fixed Coordinate System

1 Motion of the Magnetization Vector in a Fixed Coordinate System 

By multiplying eq. (1.18) with the gyromagnetic ratio y one obtains the time dependence of the magnetic moment ft, remembering that fi = yp  

For an assembly of nuclei with magnetic moment fi the resultant vector sum is the magnetization vector M. Its time dependence is also given by eq. (1.19). 

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