A series RL circuit with inductance L and resistance R is connected to an emf V. After a period of time, the current reaches a final value of 2.0 A. A second series circuit is identical except that the inductance is 2L. When it is connected to the same emf V, what will be the final value of the current?

Faraday's law: A changing magnetic field induces an emf.

Lenz's law:  current produced by an induced emf moves in a direction so that its magnetic field opposes the original change in flux.

The three ways that an emf can be induced in a loop of wire.
1. by changing the magnetic field
2. by changing the area of the loop in the field
3. by changing the loop's orientation with respect to the field