The back emf in a $DC$ motor is maximum when,

  • A
    the motor has picked up maximum speed
  • B
    the motor has just started moving
  • C
    the speed of motor is still on increase
  • D
    the motor has just been switched off

Explore More

Similar Questions

An $AC$ generator consists of a coil of $500$ turns and area $2\ m^2$ rotating at an angular speed of $30\ rad\ s^{-1}$ in a uniform magnetic field $B = 0.20\ T$ between two fixed pole pieces. The resistance of the circuit including that of the coil is $1000\ \Omega$. What is the maximum current drawn from the generator?

Armature current in a $DC$ motor will be maximum when:

An electric motor operates on a $50\,V$ supply and a current of $12\,A$. If the efficiency of the motor is $30\%$,what is the resistance of the winding of the motor in $\Omega$?

The armature of a generator of resistance $1 \,\Omega$ 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 ......... $A$.

$A$ generator has an armature resistance of $0.1 \, \Omega$ and develops an induced emf of $120 \, V$ when driven at its rated speed. Its terminal voltage when a current of $50 \, A$ is being drawn is ................. $V$.

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo