Q107 / 150 · MHT CET 2012 · Physics

The back emf in a DC motor is maximum when,

Correct answer
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

Solution

The value of back emf, $e \propto W$. So, back emf is maximum when the motor has picked up the maximum speed.

Hence, the correct answer is option: 'A'.

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