Electro Magnetic Induction And Alternating Currents Question 281
Question: A step-down transformer is used on a 1000 V line to deliver 20 A at 120 V at the secondary coil. If the efficiency of the transformer is 80% the current drawn from the line is [Kerala PET 2005]
Options:
A) 3 A
B) 30 A
C) 0.3 A
D) 2.4 A
Show Answer
Answer:
Correct Answer: A
Solution:
$ \eta =\frac{\text{Output}}{\text{Input}} $
Þ $ \frac{80}{100}=\frac{20\times 20}{1000\times i_{l}} $