The d.c. series motor should never be switched on at no load because?

The d.c. series motor should never be switched on at no load because?
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The d.c. series motor should never be switched on at no load because the speed becomes dangerously high.

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If the pole flux of a d.c. motor approaches zero, its speed will?

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The induced e.m.f. in the armature conductors of a d.c. motor is?

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The normal value of the armature resistance of a d.c. motor is?

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The counter e.m.f. of a d.c. motor?

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