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.
In terms of slip, the actual speed of the motor (N) can be expressed as N = Ns(1 − s) At start, the motor is at rest and hence its speed N is zero. s = 1 ( start) This is the maximum value of slip s possible for the induction motor which occurs at start. While s = 0 gives us N = N. which is not possible for an induction motor. So slip of the induction motor cannot be zero under any circumstances. Practically motor operates in the slip range of 0.01 to 0.05 i.e. 1 % to 5 %. The slip corresponding to the full load speed of the motor is called full load slip.
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.
When two alternating quantities of the same frequency have different zero points, they are said to have a phase difference. The angle between zero points is the angle of phase difference φ. In the above-given question, the frequency of voltage and current is different so we can’t calculate the phase difference between them
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