The magnetic field produced by a straight current-carrying conductor is in the form of concentric circles.

How is the magnetic field produced in a solenoid used?

What is the nature of the magnetic field produced by a current-carrying circular coil? Explain with the help of an experiment.

The magnetic field produced by a current in a straight wire has no poles.

What are the factors on which the magnetic field due to a current carrying solenoid depends?

$A$ magnetic compass shows a deflection when placed near a current-carrying wire. How will the deflection of the compass be affected if the current in the wire is increased? Support your answer with a reason.