two

four

equal to the no. of poles

one

steady d.c.

steady a.c.

pulsating a.c.

pulsating d.c

no effect takes place

current flow is stopped

The direction of current flow is reversed

the magnitude of current flow is decreased

rotating magnetic field past stationary coils

relative motion between the field and the armature coils

converting electrical energy into mechanical energy

rotating the coils around a magnetic field

long shunt

short shunt

differential compound

cumulative compound