DC Motors What will happen if the back emf of a dc motor vanishes suddenly? The motor will stop The armature may burn The motor will continue to run The motor will run noisy The motor will stop The armature may burn The motor will continue to run The motor will run noisy ANSWER DOWNLOAD EXAMIANS APP
DC Motors In case the conditions for maximum power for a D.C. motor are established, the efficiency of the motor will be Less than 50% Around 90% Anywhere between 75% and 90% 1 Less than 50% Around 90% Anywhere between 75% and 90% 1 ANSWER DOWNLOAD EXAMIANS APP
DC Motors For starting a dc motor a starter is required because It starts the motor It limits the starting current to a safe value It limits the speed of the motor None of the listed here It starts the motor It limits the starting current to a safe value It limits the speed of the motor None of the listed here ANSWER DOWNLOAD EXAMIANS APP
DC Motors Which of the following can be used for controlling the speed of a dc motor? Thyratron Thyristor Thermistor Transistor Thyratron Thyristor Thermistor Transistor ANSWER DOWNLOAD EXAMIANS APP
DC Motors Excessive sparking at brushes may be caused due to Worn bearings Dirt on the commutator Loose coupling Misaligment of machine Worn bearings Dirt on the commutator Loose coupling Misaligment of machine ANSWER DOWNLOAD EXAMIANS APP
DC Motors The main disadvantage of the Ward-Leonard control method is High initial cost Low efficiency at high loads All of these High maintenance cost High initial cost Low efficiency at high loads All of these High maintenance cost ANSWER DOWNLOAD EXAMIANS APP