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.

when the speed of a dc motor increase the armature current

when the speed of a dc motor increase the armature current

Armature current in dc motor will be maximum when

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 ?

The current in the armature of dc motor is the maximum when the motor is :

How can the speed of rotation of the armature coil of an electric motor be increased ?