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The power factor in a single-phase circuit (or balanced three-phase circuit) can be measured with the wattmeter-ammeter-voltmeter method, where the power in watts is divided by the product of measured voltage and current. The power factor of a balanced polyphase circuit is the same as that of any phase. The power factor of an unbalanced ...
Now, if this motor is fed with current of 2 A and assuming that back-EMF is exactly 2 V, it is rotating at 7200 rpm and the mechanical power is 4 W, and the force on rotor is = N or 0.0053 N. The torque on shaft is 0.0053 N⋅m at 2 A because of the assumed radius of the rotor (exactly 1 m).
Many useful motor relationships between time, current, voltage, speed, power factor, and torque can be obtained from analysis of the Steinmetz equivalent circuit (also termed T-equivalent circuit or IEEE recommended equivalent circuit), a mathematical model used to describe how an induction motor's electrical input is transformed into useful ...
For electrical motors, a similar kind of information is conveyed by the service factor, which is a multiplier that, when applied to the rated output power, gives the power level a motor can sustain for shorter periods of time. The service factor is typically in the 1.15-1.4 range, with the figure being lower for higher-power motors.
9mm Major is a wildcat cartridge of the 9mm Luger specifically for competition pistols designed to handle very high pressure. It is used in practical shooting competitions like International Practical Shooting Confederation (IPSC) and United States Practical Shooting Association (USPSA) to achieve a "Major" power factor, which earns more points for hits in specific zones on paper targets ...
The minimum at unity power factor () is due to the general formula for the power P of a synchronous motor, = . In order to keep the power constant, with the line voltage at the terminals of the armature V A {\displaystyle V_{A}} also constant, any decrease in power factor has to be accommodated by a corresponding increase in the armature ...
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Since most power systems of any significant size have a net lagging power factor, the presence of overexcited synchronous motors moves the system's net power factor closer to unity, improving efficiency. Such power-factor correction is usually a side effect of motors already present in the system to provide mechanical work, although motors can ...