Why do iron filings arrange themselves in a certain pattern around a magnet?

In which of the following cases will maximum electric current be induced in the loop?

Under what condition does a current-carrying conductor kept in a magnetic field experience maximum force? On what other factors does the magnitude of this force depend? Name and state the rule used for the determination of the direction of this force.

State the direction of the magnetic field inside the bar magnet.

$A$ current $I$ passes through a circular loop $C$ and a solenoid $AB$ as shown below:
$(i)$ What is the polarity of: $(a)$ the face of the loop you are looking at? $(b)$ the end $B$ of the solenoid?
$(ii)$ What is the direction of the magnetic field at the centre of the loop?

$(a)$ Mention the colour code used for live,neutral,and earth wire.
$(b)$ You want to connect a $2 \ kW$ electric oven in the electric circuit. In which power line would you connect it and why? What may happen if you connect it wrongly in the other power line?