What type of core is used to make an electromagnet?

The horizontal component of the Earth's magnetic field at a place is uniform and its direction is from south to north. $A$ high current flows through a horizontal power line at this place from west to east. Consider two points $A$ and $B$ at equal distances from the wire,respectively above and below it. Giving reasons,explain where the magnetic field is stronger: at $A$ or at $B$.

According to Fleming's right-hand rule,what is indicated by the direction of the center finger?

$A$ magnetic compass shows a deflection when placed near a current-carrying wire. How will the deflection of the compass be affected if the current in the wire is increased? Support your answer with a reason.

Differentiate between $AC$ and $DC$ along with the graph.

How is the magnetic field produced in a solenoid used?