Lenz's law, back emf, and induced current

We use an example to show that the induced current in a solenoid resulting from changing magnetic field cannot be determined by simply applying Lenz's law when the solenoid's inductance is significant. Pointing this out is worthwhile because in some examples and exercises in physics textbooks the back emf caused by the inductor is likely to be ignored by educators. Quantitative calculation shows that induced current direction is determined by magnetic field changing frequency, resistance, and inductance in the circuit.