A solenoid is connected to a battery so that a steady current flows through it. If an iron core is inserted into the solenoid, will the current increase or decrease? Explain.
Hint: The current in the coil depends on the core of the solenoid.
When the iron core is inserted in the current-carrying solenoid, the magnetic field increase due to the magnetization of iron core and consequently the flux increases.
According to Lenz's law, the emf produced must oppose this increase in flux, which can be done by making a decrease in current. So, the current will decrease.
