For the circuit shown in Fig. Which of the following statements are correct?

Options

A. Its time constant is 0.25 s
B. In steady sate, current through inductance will be equal to zero
C. In steady state, current through the battery will be equal to 0.75 A
D. None ot the above.

Answer

A, C

Explanation

In the circuit shown in figure of the question, `6 Omega` and `12 Omega` resistance are in parallel combination is in series with `4 Omega` and the inductance of 2H. Hence, equivalent resistance of these three resistance is equal to `8 Omega`. Therefore, this circuit may be reduced to the circuit as shown in fig.
The time constant for the circuit is
`tau=(L)/(R)=2/8 = 0.25 sec`.
Hence, option (a) is correct.
In steady state, no emf will be induced in the inductance. Hence, current through the circuit will be equal to `E//R` where R is equivalent resistance. Hence, the steady state current will be equal to `6/8=0.75 amp`.
Hence, option (c) is correct and (b) is wrong.