On which principle does an electric bell work?

Describe the activity that shows that a current-carrying conductor experiences a force perpendicular to its length and the external magnetic field. How does Fleming's left-hand rule help us to find the direction of the force acting on the current-carrying conductor?

$A$ coil of insulated wire is connected to a galvanometer. Explain what happens if a bar magnet with its north pole towards one face of the coil is:
$(i)$ moved quickly towards the coil,
$(ii)$ kept stationary inside the coil,and
$(iii)$ moved quickly away from the coil?

Explain with the help of a labelled diagram the distribution of magnetic field due to a current through a circular loop. Why is it that if a current-carrying coil has $n$ turns,the field produced at any point is $n$ times as large as that produced by a single turn?

State Faraday's second law of electromagnetic induction.

Under what conditions is a permanent magnet obtained if a current-carrying solenoid is used? Support your answer with the help of a labelled circuit diagram.