Electrical Machines When the armature current of 5 Amp is flowing through the dc motor the torque produced is 47 Nm. Keeping the speed constant if the armature current is increased to 7 amp, calculate the new torque. Assume losses to be constant. 65.8 Nm. 27.73 Nm . 74 Nm. 38.5 Nm. 65.8 Nm. 27.73 Nm . 74 Nm. 38.5 Nm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Eb/Vt ratio of a DC motor is an indication of running torque. starting torque. efficiency. speed regulation. running torque. starting torque. efficiency. speed regulation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The brushes of a DC machine should be placed on the armature in the polar axis. commutator in the polar axis. armature midway between poles. commutator in the inter polar axis. armature in the polar axis. commutator in the polar axis. armature midway between poles. commutator in the inter polar axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines How can the synchronous speed of a 3 - Φ IM be varied? By varying supply voltage. Both (A) and (B). By varying number of poles. By varying the supply frequency. By varying supply voltage. Both (A) and (B). By varying number of poles. By varying the supply frequency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC motor with armature resistance of 0.5 ohms is connected directly to a 230 Volt supply. If the armature is stationary then the current flowing through armature is 340 A. 460 A. 250 A. 570 A. 340 A. 460 A. 250 A. 570 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the full load speed of 3-phase, 50Hz induction motor is 950 rpm, what is its half load speed nearly equals to? 950 rpm 940 rpm 1000 rpm 975 rpm 950 rpm 940 rpm 1000 rpm 975 rpm ANSWER DOWNLOAD EXAMIANS APP