Question is ⇒ The mechanical power developed by a D.C. motor is equal to, Options are ⇒ (A) power input + losses, (B) back e.m.f. X armature current, (C) power output X losses, (D) power output X efficiency, (E) , Leave your comments or Download question paper.

Question is ⇒ The mechanical power developed by a D.C. motor is equal to, Options are ⇒ (A) power input + losses, (B) back e.m.f. X armature current, (C) power output X losses, (D) power output X efficiency, (E) , Leave your comments or Download question paper. Previous question Next question


Q1.	The mechanical power developed by a D.C. motor is equal to
A.	power input + losses [Wrong Answer]
B.	back e.m.f. X armature current [Correct Answer]
C.	power output X losses [Wrong Answer]
D.	power output X efficiency [Wrong Answer]
View Answer 11 -9 Explanation:- Answer : B Discuss it below : Kapil Kaushik Said on 2022-02-27 03:10:59 The voltage equation of a dc motor is V = E_b + I_aR_a Here, V = Applied voltage, E_b = Back or Counter e.m.f, R_a = Armature resistance, I_a = Armature current, Now, power equation of dc motor is multiplying the above equation by armature current VI_a= E_bI_a + I²_aR_a Here, E_bI_a is the power developed by the armature (armature output),VI_a = electric power supplied to armature (armature input) , I²_aR_a= electric power wasted in the armature (armature Copper loss) E_bI_a is the mechanical power developed by the dc motor Hence, option (B) back e.m.f × armature current - is the right answer !! OOPS Login [Click here] is required to post your answer/result Help other students, write article, leave your comments

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