A coil of `40 H` inductance is connected in series with a resistance of `8` ohm and the combination is joined to the terminals of a `2 V` battery. The time constant of the circuit

An inductance of 2 H and resistance of 10 Omega are connected to a battery of 5 V. the time constant of the circuits is:

An inductance of 2 H and resistance of 10 Omega are connected to a battery of 5 V. the time constant of the circuits is:

A coil of inductive reactance 31 Omega has a resistance of 8 ohm . It is placed in series with a condenser of capacitive reactance 25 Omega . The combination is connected to an ac source of 110 V . The power factor of the circuit is

A coil of inductive reactance 31 Omega has a resistance of 8 ohm . It is placed in series with a condenser of capacitive reactance 25 Omega . The combination is connected to an ac source of 110 V . The power factor of the circuit is