A motor having an armature of resistance 2.0 ohm operates on 220 V mains. At its full speed, it develops a back e.m.f. of 210 V. Find the currents in the armature when motor is switched on and when running at full speed. What is the efficiency ot the motor at full speed ?

A motor having an armature of resistance 2.0 Omega operates on 220 V mains. At full speed, it develops a back emf of 210 V. Find the current in the armature just when the motor is switched on (assuming that no starter is used) and when running at full speed. Also fined the efficiency of the motor at full speed.

A motor having an armature of resistance 2Omega is designed to operate at 220 V mains. At full speed, it devlops a back e.m.f. of 210V . When the motor is running at full speed, the current in the armature is

A motor runs at 20 V. The resistance of the armature is 11 ohm. If the back emf produced is 198 V, when at full speed, then calculate the current through armature, when (i) motor is just switched on and (ii) motor is at full speed.

A generator develops an e.m.f. of 120 V and has a terminal potential difference of 115 V, when the amature current is 25 A. What is the resistance of the armature ?

A motor has an armature resistance of 4 ohm. On a 240 V supply and a light load, the motor speed is 200 rpm and the armature current is 5 A Calculate the motor speed at a full load. When armature current is 20 A.

The resistance of the armature of an electric motor is 55 ohm. The motor draw a current of 2 A when running at 220 V. What is the back e.m.f ?

The armature of a generator of resistance 1Omega is rotated at its rated speed and produces 125 V without load and 115 V with full load. The current in the armature coil is

The armature of a generator of resistance 1Omega is rotated at its rated speed and produces 125 V without load and 115 V with full load. The current in the armature coil is

when the speed of a dc motor increase the armature current