Electro Magnetic Induction And Alternating Currents Question 249
Question: A transformer is employed to reduce 220 V to 11 V. The primary draws a current of 5 A and the secondary 90 A. The efficiency of the transformer is [MP PMT 1992, 2001, 04]
Options:
A) 20%
B) 40%
C) 70%
D) 90%
Show Answer
Answer:
Correct Answer: D
Solution:
$ \eta =\frac{V_{s}i_{s}}{V_{p}i_{p}}\times 100=\frac{11\times 90}{220\times 5}\times 100=90\ % $
