Tip:
Highlight text to annotate it
X
All right, so instead of accelerating atoms, we're going to be accelerating
some Rice Krispies.
And so the first thing I'm going to have you do is I'm going to have you
step up on this insulating column,
so that the charge the builds up on you doesn't recombine with the
opposite charge on the ground.
And I'll have you put your hand on this metal sphere, so that the charge
that's collected on the sphere of the Van de Graaff also is conducted onto
you as well.
And I' m going to have you hold out your left palm, and I'm going to pour
some Rice Krispies in there.
And I'm going to have you gently close your hand.
I'm going to turn the Van de Graaff generator on so that you're negatively
charged, as well as the Rice Krispies.
And then I'm going to have you gently open up your hand and flatten out your
palm as you extend your arm,
so we'll see what effect all that negative charge has on the Rice
Krispies and you.
You ready, Dave?
I'm ready.
All right, here we go.
All right, extend your arm and open up your fingers.
So all the charge on the Rice Krispies is repelled by the like charge on your
palms, demonstrating that like charges repel.
So if you reach out a knuckle, then we'll see that even though you don't
look-- you don't seem to be charged, those charges are invisible.
They were silent.
But whenever you came close enough to me, the negative charge on you
was neutralized by opposite positive charge that came up from the
ground and to me.
That neutralization probably wasn't complete.
Got another one, but that one was considerably smaller than the first.
And if we do it again, nothing.
Back to normal.