Last week I did this demo to my pupils: I built a non-magnetic metal cage for
a radio. Kids loved to hear its music vanishing when I closed it. That was OK
for FM.
Suddenly one kid asked me to try it again with AM. I thought it would make no
difference at all, but OOPS!!!, the music did not vanished completely, and I
could not explain the reason...
Does anybody know it?
PS. The cage is made of aluminium wire mesh.(aprox. 4mm side squares)