A D.C. motor working on 200V have initial current of 5A but when it attained maximum velocity, the current obtained is 3A. What will be its Back emf ?

A D.C. motor working on 200V have initial current of 5A but when it at

1.	A D.C. motor working on 200V have initial current of 5A but when it attained maximum velocity, the current obtained is 3A. What will be its Back emf ?
Answer» 0V 80 V 120 V 200 V Solution :`R=E/I=200/5=40 Omega` Now `I=(E-EPSILON)/R rArr 3= (200-epsilon)/40` `therefore120=200-epsilon` `THEREFORE epsilon` =80 V

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A D.C. motor working on 200V have initial current of 5A but when it attained maximum velocity, the current obtained is 3A. What will be its Back emf ?

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