Electrical Machines The damper windings also called the squirrel cage windings or damper grids both (A) and (B). are provided on the stator for improving power factor. consists of short-circuited copper bars embedded in the field pole faces. are provided in a synchronous motor to make it self starting. both (A) and (B). are provided on the stator for improving power factor. consists of short-circuited copper bars embedded in the field pole faces. are provided in a synchronous motor to make it self starting. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V DC series motor takes 40 A when giving its rated output at 1500 rpm. Its resistance is 0.3 ohms. The value of resistance which must be added to obtain rated torque at 1000 rpm is 1.9 ohms. 2.2 ohms. 5.7 ohms. 6 ohms. 1.9 ohms. 2.2 ohms. 5.7 ohms. 6 ohms. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The shaft torque of a dc motor is less than the electromagnetic torque because of eddy current losses. ohmic losses. hysteresis losses. mechanical losses. eddy current losses. ohmic losses. hysteresis losses. mechanical losses. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the load current and flux of a DC motor are held constant and voltage applied across it armature is increased by 5%, the speed of the motor will Increase by 5%. Reduce by 5%. Depends on other factor. Remain unchanged. Increase by 5%. Reduce by 5%. Depends on other factor. Remain unchanged. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC Shunt Motor having shunt field resistance of 250 Ω and armature resistance of 0.5 Ω is connected to 250 V supply and load current of 21 A. What is the back emf generated ? 150 V. 230 V. 210 V 240 V. 150 V. 230 V. 210 V 240 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A motor armature conductor of length 0.5 m is exposed to a flux density of 4 Wb / m2. Calculate the force experienced by the conductor, when the armature current is 5 Amp? 15 N. Can't be determined. None of these. 20 N. 15 N. Can't be determined. None of these. 20 N. ANSWER DOWNLOAD EXAMIANS APP