Electro Magnetic Induction And Alternating Currents Question 525
Question: A coil is wound as a transformer of rectangular cross-section. If all the linear dimensions of the transformer are increased by a factor 2 and the number of turns per unit length of the coil remain the same, the self inductance increased by a factor of [AIIMS 1980]
Options:
A) 16
B) 12
C) 8
D) 4
Show Answer
Answer:
Correct Answer: C
Solution:
Self inductance $ L={\mu_{0}}N^{2}A/l={\mu_{0}}n^{2}lA $
Where n is the number of turns per unit length and N is the total number of turns and $ N=nl $
In the given question n is same.
A is increased 4 times and l is increased 2 times and hence L will be increased 8 times.
