The torque of a rotor in an induction motor under running condition is maximum__________?
Correct answer: C. at the value of the slip which makes rotor reactance per phase equal to the resistance per phase
- A. at the unit value of slip
- B. at the zero value of slip
- C. at the value of the slip which makes rotor reactance per phase equal to the resistance per phase
- D. at the value of the slip which makes the rotor reactance half of the rotor
Explanation
Maximum induction-motor torque occurs when the effective rotor reactance equals rotor resistance, so sX₂ = R₂. This is the condition represented by option c.
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