Not start
Run at $$ rac{2}{3}$$ of synchronous speed
Run with excessive vibrations
Take less than the rated load
Answer is Right!
Answer is Wrong!
The correct answer is: A. Not start
A three-phase synchronous motor requires a three-phase supply to operate. If one phase is short-circuited, the motor will not start because there is no current flowing in the short-circuited phase. The motor will not be able to develop a rotating magnetic field and will not start.
Option B is incorrect because the motor will not run at $\frac{2}{3}$ of synchronous speed. The motor will not start at all.
Option C is incorrect because the motor will not run with excessive vibrations. The motor will not start at all.
Option D is incorrect because the motor will take less than the rated load. The motor will not start at all.