Q. In DC machines the residual magnetism is present. The order of residual magnetism is ___________

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Q. Sparking is discouraged in a DC motor.

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Q. Which of the following motor is used where high starting torque and wide speed range control is required?

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Q. The armature voltage control of DC motor will provide ___________

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Q. As there is no back emf at the instant of starting a DC motor, in order to prevent a heavy armature current from flowing though the armature circuit ___________

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Q. What will happen to torque if back emf and speed of the DC motor is doubled?

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Q. At the instant of starting, when a DC motor is put on supply, it will behave like ______________

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Q. All others are advantages of DC motor over AC motor except _______________

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Q. If a DC motor designed for 45°C ambient temperature is to be used for 55°C ambient temperature, then the motor ___________

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Q. Torque developed by a DC motor depends upon _____________

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Q. For very sensitive and wide speed control, which of the following method is preferred?

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Q. Field weakening control method is used for the speed _________

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Q. Armature resistance control method is used for the speed _____________

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Q. Which function is performed by counter emf of a DC motor?

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Q. The output power of any electrical (AC or DC) motor is taken from the ______________

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Q. Why field winding of a DC series motor is provided with thick wire?

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Q. Why starters are required in a DC motor?

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Q. For which motors DOL starter can be used?

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Q. A three-point starter is used for _________

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Q. The starting resistance of a DC shunt motor is generally ______

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