Electrical Machines In case of a dc motor the ratio Eb / E is indicative of efficiency. ratio of starting to running current. ratio of input to output voltage. ratio of starting to running torque. efficiency. ratio of starting to running current. ratio of input to output voltage. ratio of starting to running torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The condition for maximum running torque is R = S.X 0.5 lagging unity zero 0.707 lagging R = S.X 0.5 lagging unity zero 0.707 lagging ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor is running at rated speed without any additional resistance in series. If an additional resistance is placedin series, the speed of motor Increases. Remains unchanged. Oscillates around the rated speed. Decreases. Increases. Remains unchanged. Oscillates around the rated speed. Decreases. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An induction motor when started on no load does not accelerate up to full speed but runs at 1/7th of the rated speed. The motor is said to be cogging. plugging. locking. crawling. cogging. plugging. locking. crawling. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In Ward-Leonard method of speed control, the direction of rotation of motor is reversed usually reversing the connection of the generator armature terminal. generator field terminal. motor armature terminal. motor field terminal. generator armature terminal. generator field terminal. motor armature terminal. motor field terminal. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 12 pole, 600 V, 50 Hz star connected IM has rotor resistance and stand still resistance of 0.03 Ω and 0.5 Ω respectively. The speed of maximum torque will be 470 rpm. 240 rpm. 450 rpm. 540 rpm. 470 rpm. 240 rpm. 450 rpm. 540 rpm. ANSWER DOWNLOAD EXAMIANS APP