Atoms or ions with unpaired electrons are attracted to a magnetic field; the more unpaired electrons, the greater is the attraction. Such substances are called paramagnetic. Molecular oxygen is a paramagnetic gas by virtue of its two unpaired electrons.
Phosphorus (P) has 15 electron i.e 2,8,5. Hence the number of electron in its outermost orbit is 5. Silicon (Si) has 14 electron i.e 2,8,4. Hence the number of electrons in its outermost orbit is 4.
The commutator is a feature of d.c.motors. But a.c. motors having wound rotor with brushes and commutator arrangements, are called commutator motors that work on single-phase a.c. supply. The commutator arrangement present in these motors is similar to the armature of a d.c. motor.E.g. of single-phase commutator type induction motor is Repulsion Motor Repulsion-Induction Motor AC Series Motor Universal Motor
EXAMIANS