The total power crossing the air gap (Pag) of a four-pole, 60-Hz induction motor during startup is 30.75 kW. What is the starting torque?
Explanation
The torque developed by an induction motor is directly related to the power transferred across the air gap from the stator to the rotor. The relationship is Tdev = Pag / ωs, where ωs is the synchronous angular speed. This formula is valid at any speed, including startup (s=1).
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