Question

for a simple motor why must the back emf always be smaller than the applied potential difference?​

Answer 1

Answer:

Back EMF is less than the applied voltage because of the resistance of the armature winding. In the above circuit the Back emf can be written as, Therefore, Now in the above equation if the value of current is negative then back emf can be higher than the applied voltage, which is the case for the generators.

Explanation:

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