-
...and that's coming up after this.
-
[recorded tagline]: 96.3!
-
--As a radio DJ, I'm surrounded
by permanent magnets all the time--
-
like this one here,
found in my headphones...
-
and these, found in the big speakers.
-
And there's even one in this microphone.
-
[birdsong]
-
--And would you believe
-
there's a link between cows and magnets,
as our vet explains?
-
--The cow magnet will sit in
the front stomach of the cow,
-
where it can attract
hazardous pieces of metal--
-
like this bit here, which the cow
may eat by mistake.
-
While this piece of metal can
roam free in the cow's stomach,
-
it could puncture the stomach wall
and cause the cow a lot of harm...
-
but while it remains attached
to the magnet, it can cause no harm at all.
-
--Permanent magnets are useful,
-
but sometimes you need a magnet
that can be controlled:
-
a magnet that can be switched on and off,
like the one at the scrap yard.
-
It helps to move bits of metal
from one place to another.
-
Doctors use temporary magnets, too.
-
--As an eye surgeon, sometimes
we have to remove tiny bits of metal
-
which become embedded in
the backs of people's eyes.
-
And if you look at this x-ray,
you can see this tiny little fragment
-
here at the back of this person's eye;
and this could cause serious damage.
-
And we remove those fragments
using an electromagnet, like this one.
-
Now here we see,
with the electromagnet off,
-
it's not able to lift up a bit of metal
like this paper clip.
-
But when I turn the magnet on,
we're able to lift up that paper clip.
-
And that's how, as an eye surgeon,
we use electromagnets
-
to remove bits of metal from the eye.
-
--Magnetism gets everywhere!
-
--There's a magnet in anything
-
that has a motor,
like your hair dryer or microwave.
-
There's a magnet in your telephone!
-
In a computer!
-
In a video recorder--and your TV!