The torque speed characteristic of a repulsion motor resembles which of the following d.c. motor

The torque speed characteristic of a repulsion motor resembles which of the following d.c. motor characteristics 

A) Separately excited B) Shunt C) Series D) Compound
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The torque speed characteristic of a repulsion motor resembles which of the following d.c. motor characteristics Series 

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Speed control of a universal motor is achieved by?

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