A source of constant voltage V is connected to a resistance R and...
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?
As L1 and L2 are in parallel so equivalent
inductance, L=L1L2L1+L2
Here, L1 and L2 are the inductance (shown in circuit)
The current through the RL series circuit at anytime is given as
I= VR(1-e-RtL)
At t=0,
I=VR(1-e0)=0
After a longtime i.e. at t=∞
I=VR(1-e-∞)
⇒I=VR
Let currents through L1 and L2 are I1 and I2 respectively. As L1 and L2 are joined in parallel
Voltage across L1= Voltage across L2
⇒VL1=VL2
⇒L1dI1dt=L2dI2dt
⇒L1I1=L2I2
Thus, I1I2=L2L1
By current division rule,
Current I1 across L1 is
I1=L2L1+L2×I
⇒I1=VR(L2L1+L2)
Current I2 across L2 is
I2=L1L1+l2×I
I2=VR(L1L1+L2)
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