Electrical Machines If the armature electric current is increased to double its previous value, and the time of commutation is halved, how will the reactance voltage vary? It will be halved. It will be doubled. It will remain the same. It will becomes four times. It will be halved. It will be doubled. It will remain the same. It will becomes four times. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature reaction in a DC machine is in direct opposition to the main poles. is in the same direction as the main poles. makes an angle of 90° with the main pole axis. makes an angle with the main pole axis which is load dependent. is in direct opposition to the main poles. is in the same direction as the main poles. makes an angle of 90° with the main pole axis. makes an angle with the main pole axis which is load dependent. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Thin laminations are used in a machine in order to reduce Hysteresis losses Eddy current losses Copper losses Both 1 and 2 Hysteresis losses Eddy current losses Copper losses Both 1 and 2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed regulation of a DC motor is given as NnL − NfL. (NnL − NfL)/NfL. (NfL − NnL)/NnL. NnL/NfL. NnL − NfL. (NnL − NfL)/NfL. (NfL − NnL)/NnL. NnL/NfL. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a loaded DC motor, if the brushes are given a shift from the interpolar axis in the direction of rotation, then the commutation will deteriorate and the speed rises. improve and the speed rises. improve and the speed falls. deteriorate and the speed falls. deteriorate and the speed rises. improve and the speed rises. improve and the speed falls. deteriorate and the speed falls. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The commutator segments of DC machines are made up of hard-drawn copper copper alloy brass copper hard-drawn copper copper alloy brass copper ANSWER DOWNLOAD EXAMIANS APP
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