In a region where magnetic field lines are close to each other,what is the nature of the magnetic field?

Explain why a fuse should be joined with the live wire and not with the neutral wire in a domestic circuit.

$(a)$ $A$ coil of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is:
$(i)$ pushed into the coil with its north pole entering first?
$(ii)$ withdrawn from inside the coil?
$(iii)$ held stationary inside the coil?
$(b)$ Name the above phenomenon and mention the name of the scientist who discovered it. State the law that relates the direction of current in the coil with the direction of motion of the magnet.

Why does a magnetic compass needle pointing North and South in the absence of a nearby magnet get deflected when a bar magnet or a current carrying loop is brought near it? Describe some salient features of magnetic lines of field concept.

$A$ circular loop placed in a plane perpendicular to the plane of paper carries a current when the key is $ON$. The current as seen from points $A$ and $B$ (in the plane of paper and on the axis of the coil) is anti-clockwise and clockwise respectively. The magnetic field lines point from $B$ to $A$. The $N-$ pole of the resultant magnet is on the face close to

Which type of magnet is used in a crane to lift cars?