Who first observed the magnetic effect of an electric current?

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

Fleming's right-hand rule can be used to find the direction of the magnetic field.

$(a)$ What are magnetic field lines? How is the direction of a magnetic field at a point determined?
$(b)$ Draw two field lines around a bar magnet along its length on its two sides and mark the field directions on them by arrow marks.
$(c)$ List any three properties of magnetic field lines.

The laws of electromagnetism tell us that energy can be transferred from one object to another:

Suggest one way of discriminating a wire carrying current from a wire carrying no current.