Answer / sabyasachi mishra

If a dc series motor will start with load then its rotor
will rotate at enermous speed .
As we know speed(N) is directly propertional to back emf
(Eb) of motor and inversely propertional to flux generated.
So initially the motor will drawn less or no
current,hence the speed will reach at a dangerious limit.
Hence a dc series motor never started without load.

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