We use universal motors in mixer grinders. Universal motors can run both on a.c. and d.c. The universal motor works on the same principle that DC series motor works. DC series motor has the characteristics of operating at high-speed when there is no load and operating at low-speed when the load is applied. It has high starting torque characteristics. So it is used in mixers, where initially we put some load at starting.
The amount of flux produced by the magnet indicates the strength of the magnet. The more the magnetizing force (MMF), the more is the flux produced. The more the opposition to the flux path (i.e., reluctance or magnetic resistance) less is the flux produced. This relationship is expressed as Flux = MMF/ Reluctance Reluctance is the opposition offered by the material in the flux path to the establishment of the flux. The reluctance in a magnetic circuit is similar to the resistance in an electric circuit. Reluctance is the inverse of permeance. MMF = Flux/Permeance
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.
EXAMIANS