question_answer

An inductor, three resistors and a battery of 90 volt are connected in circuit as shown. Switch 'S" is closed for a long time, let the current in \[10\Omega \] is\[{{i}_{1}}\]. Now switch 'S" is suddenly opened, let the current in  \[10\Omega \] is \[{{i}_{2}}\]. The ratio of \[{{i}_{1}}/{{i}_{2}}\] is

A) \[1\]                        

B)        \[3\]                

C) \[4.5\]                    

D)        \[1.5\]

Correct Answer: B

Solution :

[b] At steady state, \[{{i}_{1}}=4.5amp\] After switch is opened \[{{i}_{2}}=1.5\,amp\] \[\frac{{{i}_{1}}}{{{i}_{2}}}=3\]