$A$ soft iron bar is introduced inside a current-carrying solenoid. The magnetic field inside the solenoid:

How can you magnetise a piece of magnetic material?

Name the rule used to find the direction of force on a current-carrying conductor placed in a magnetic field.

$A$ device used for producing current is:

The electric current that always flows in the same direction is called alternating current.

$(a)$ Draw magnetic field lines of a bar magnet. "Two magnetic field lines never intersect each other". Why?
$(b)$ An electric oven of $1.5 \, kW$ is operated in a domestic circuit $(220 \, V)$ that has a current rating of $5 \, A$. What result do you expect in this case? Explain.