The magnetic field around a current-carrying straight conductor is:

The flow of a current in a circular loop of a wire creates a magnetic field at its centre. How can the existence of this field be detected? State the rule which helps to predict the direction of this magnetic field.

$A$ straight conductor passes vertically through a cardboard sprinkled with iron filings. Show the setting of iron filings when a weak current is passed in the downward direction and then the cardboard is gently tapped. Draw arrows to represent the direction of magnetic field lines.
What changes occur if,
$(i)$ the strength of current is increased?
$(ii)$ the single conductor is replaced by several parallel conductors each carrying same current flowing in the same direction?

The strength of the magnetic field of a solenoid does not depend upon:

What are the safety measures to be taken while dealing with household electricity?

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