The relative speed between the stator magnetic field and rotor in the synchronous generator is ______

The relative speed between the stator magnetic field and rotor in the

1.	The relative speed between the stator magnetic field and rotor in the synchronous generator is ______
A.	N<sub>s</sub>
B.	N<sub>s</sub>-N<sub>r</sub>
C.	N<sub>s</sub>+N<sub>r</sub>
D.	0
Answer» E.