An alternating electric current has a frequency of $50 \ Hz$. How many times does it change its direction in one second (in $\times$)?

Identify the poles of the magnet in the given figures $(1)$ and $(2).$

$A$ uniform magnetic field exists in the plane of paper pointing from left to right as shown in Figure. In the field,an electron and a proton move as shown. The electron and the proton experience:

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

$(i)$ $A$ compass needle gets deflected when brought near a current-carrying conductor. Why?
$(ii)$ What happens to the deflection of the needle when the current in the conductor is increased?

$(a)$ 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.