Find the time constant for the following circuit

Find time constant of the following circuits. (a) (b) (c ) (d)

The time constant for the given circuit is

The figure shows an L-R circuit the time constant for the circuit is

The figure shows an L-R circuit the time constant for the circuit is

A coil of inductance 2 H and resistance 10 Omega are in a series circuit with an open key and a cell of constant 100 V with negligible resistance. At time i = 0 , the key is closed. Find (a) the time constant of the circuit. (b) the maximum steady current in the circuit. (c) the current in the circuit at f =1 s .

A coil of inductance 2 H and resistance 10 Omega are in a series circuit with an open key and a cell of constant 100 V with negligible resistance. At time i = 0 , the key is closed. Find (a) the time constant of the circuit. (b) the maximum steady current in the circuit. (c) the current in the circuit at f =1 s .

A 40 mH coil is joined to 2 eV battery through 1M Omega resistance. Find the time constant of the circuit. What is the maximum current that is established.

In the transient shown the time constant of the circuit is :