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A source of constant voltage V is connected to a resistance R and two ideal inductors  L1 and L2 through a switch S as shown. There is no mutual inductance between the two inductors. The switch S is initially open. At t=0, the switch is closed and current begins to flow. Which of the following options is/are correct?

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a
After a long time, the current through  L1 will be VRL2L1+L2
b
After a long time, the current through L2  will be VRL1L1+L2
c
The ratio of the currents through L1 and L2 is fixed at all times t>0
d
At t=0, the current through the resistance R is VR

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detailed solution

Correct option is A

After a long time, t=∞, inductor behaves as conducting wire i=VR  and L1i1=L2i2 and i=i1+i2⇒i1=L2L1+L2i=VRL2L1+L2 and i2=VRL1L1+L2 At t=0, inductor behaves like infinte resistance, so no current pass through resistor.


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