Question

By using a compass needle, how will you know whether an iron bar is a magnet or not?
by using compass needle how will you know whether an iron bar is magnet or not ​

Answer 1

If compass needle turn toward bar it means it is a magnet but if don't show any movement it means it is not a magnet.

Answer 2

when we bring the compass needle near the iron bar it deflects if magnetic field is produced by the iron bar.if the bar dors no produced any magnetic field the compass needle will not get deflected. By this way we can conclude whether an iron bar is a magne or not