Electro Magnetic Induction And Alternating Currents Question 234
Question: The armature of dc motor has $ 20,\Omega $ resistance. It draws current of 1.5 ampere when run by 220 volts dc supply. The value of back e.m.f. induced in it will be [MP PMT 1999]
Options:
A) 150 V
B) 170 V
C) 180 V
D) 190 V
Show Answer
Answer:
Correct Answer: D
Solution:
$ i=\frac{E-e}{R}\Rightarrow 1.5=\frac{220-e}{20}\Rightarrow e=190\ V $
