How can iron filings provide evidence that a bar manet has a magnetic field? hey

The iron filings outline the magnetic field lines, making it visible. Magnetic fields all have a pair of "poles", from which "lines of force" or magnetic field lines appear to originate.

Explanation:

Iron fillings can provide evidence that a bar magnet has a magnetic field because iron filling quickly aligns in the design of the magnetic field.  It is the same with the Earth’s magnetic field

world war i had a devastating effect on german-americans and their cultural heritage. up until that point   german-americans, as a group, had been spared much of the discrimination, abuse, rejection, collective mistrust experienced by so many different racial and ethnic groups in the history of the united states. indeed, over the years, they had been viewed as a well integrated and esteemed part of american society. all of this change with the outbreak of war.