A 16-V Battery Is Connected in Series with a Switch,resistor

question 1

Multiple Choice

A 16-V battery is connected in series with a switch,resistor and coil.If the circuit's time constant is 4.2 × 10−⁴ s and the final steady current after the switch is closed becomes 2.9 A,what is the value of the inductance?

• A) 19 mH
• B) 2.3 mH
• C) 0.76 mH
• D) 1.1 mH
• E) ​7.6 mH