It is advised not to run dc series motor with no load. Why?(a) Because zero torque at no load will make speed infinite(b) Because zero torque as no load will not let machine start(c) Because infinite torque will be produced(d) None of the mentionedThe question was posed to me during an online exam.I would like to ask this question from Operating Characteristics of DC Motors in portion DC Motors of Electrical Machines

It is advised not to run dc series motor with no load. Why?(a) Because

1.	It is advised not to run dc series motor with no load. Why?(a) Because zero torque at no load will make speed infinite(b) Because zero torque as no load will not let machine start(c) Because infinite torque will be produced(d) None of the mentionedThe question was posed to me during an online exam.I would like to ask this question from Operating Characteristics of DC Motors in portion DC Motors of Electrical Machines
Answer» The correct OPTION is (a) Because zero torque at no load will MAKE SPEED INFINITE Best explanation: If the torque is zero in dc series motor then the speed will be infinite causing the damage of the machine permanently.

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