Electro Magnetic Induction And Alternating Currents Question 530
Question: The coefficient of self inductance of a solenoid is 0.18 mH. If a crode of soft iron of relative permeability 900 is inserted, then the coefficient of self inductance will become nearly
Options:
A) 5.4 mH
B) 162 mH
C) 0.006 mH
D) 0.0002 mH
Show Answer
Answer:
Correct Answer: B
Solution:
$ L=\mu ni $
Þ $ \frac{L_{2}}{L_{1}}=\frac{\mu }{{\mu_{0}}} $ ( n and i are same)
Þ $ L_{2}={\mu_{r}}L_{1}=900\times 0.18=162,mH $