An iron bar can be magnetized easily by aligning it
Chapter 9, Problem 32(choose chapter or problem)
An iron bar can be magnetized easily by aligning it withthe magnetic field lines of Earth and striking it lightly a fewtimes with a hammer. This works best if the bar is tilteddown to match the dip of Earths magnetic field. The hammeringjostles the domains so that they can better align withEarths field. The bar can be demagnetized by striking itwhen it is in an eastwest direction.
Unfortunately, we don't have that question answered yet. But you can get it answered in just 5 hours by Logging in or Becoming a subscriber.
Becoming a subscriber
Or look for another answer