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AUDIENCE: [INAUDIBLE]

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MARK HARTMAN: OK.

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So electrons that
are bound to atoms

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are only allowed to
orbit in certain states,

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or at certain energies,
with certain energies.

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OK?

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That's an important thing.

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That's what we
mean-- did anybody

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read about what a quantum was?

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How does that have to do
with what Steve just said?

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What do you think, Peter?

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AUDIENCE: Quantum is
the amount of energy

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that allows them to jump
between the energy levels.

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MARK HARTMAN: OK.

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A quantum leap is to
jump between one energy

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level of an atom--

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or an electron in a particular
energy level in an atom,

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00:01:06,470 --> 00:01:08,220
and it can jump to
the next higher level.

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All right?

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00:01:08,720 --> 00:01:10,969
Azif, what was the one or
two things that you learned?

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00:01:13,410 --> 00:01:16,450
I need everybody else to stop
clicking, to stop reading.

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We want to be paying
attention to the group.

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Nice and loud.

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AUDIENCE: When electrons
jump down a level,

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it gives out photons.

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The bigger the orbit,
the higher the energy.

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MARK HARTMAN: OK.

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00:01:29,660 --> 00:01:32,150
The bigger the orbit,
the higher the energy

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00:01:32,150 --> 00:01:34,130
that that electron has to have.

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If the electron is in a
high energy orbit and then

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it spontaneously jumps down--

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which happens, because
most things in the universe

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want to be in low
states of energy.

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00:01:45,590 --> 00:01:49,620
Being in a high state
of energy is not stable.

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00:01:49,620 --> 00:01:52,560
So when you have electrons that
are at high energy levels--

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which is why I was very
careful before to not let

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you say photons
have energy levels.

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00:01:56,990 --> 00:01:59,960
Photons do not
have energy levels.

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Photons have a certain amount
of energy, not an energy level.

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00:02:03,730 --> 00:02:05,030
OK?

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00:02:05,030 --> 00:02:07,244
I want everybody to stand up.

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00:02:07,244 --> 00:02:08,660
We're going to go
across the room,

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and we are going to do
another kinesthetic model.

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Can anybody remind you
what a kinesthetic model

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00:02:14,240 --> 00:02:16,370
is as we go across the room?

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Come over here.

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And we are all going to
be atoms of Shekibium.

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OK?

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00:02:27,800 --> 00:02:31,250
Shekibium is a
special element that

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only exists here at the CAI.

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00:02:33,890 --> 00:02:36,560
Each one of you is
going to represent

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an electron that is orbiting
around a nucleus of Shekibium.

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OK?

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And the energy
levels of Shekibium--

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if you are an electron--
so each one of us

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is going to represent
an electron orbiting

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in a different atom.

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So you can either be
in a small orbit, which

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means you have one
electron volt of energy,

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or you can be in the
next higher orbit--

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the next larger
orbit that we saw.

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Larger orbits have
higher energies.

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Three electron volts.

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Or you can be in the next higher
orbit, and you as an electron

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have to have 4 electron volts.

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OK?

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AUDIENCE: All right.

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00:03:26,720 --> 00:03:32,340
MARK HARTMAN: But we
are-- where are our cups?

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AUDIENCE: Want them all?

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MARK HARTMAN: Yup.

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Let's bring them over.

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Everybody gets a cup.

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No, you're not
going to eat M&M's.

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You're going to give them away.

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AUDIENCE: [MOANING]

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MARK HARTMAN: The ones
that you don't eat

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you don't have to give away.

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OK.

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Everybody gets one of these.

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So we're going to pretend
to be a box of Shekibium.

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00:03:53,850 --> 00:03:58,770
If our box of Shekibium
has no extra energy,

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00:03:58,770 --> 00:04:02,975
where are all the
electrons going to be?

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00:04:02,975 --> 00:04:03,727
Nice and loud.

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00:04:03,727 --> 00:04:05,560
AUDIENCE: Oh, I was
just thinking to myself.

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00:04:05,560 --> 00:04:06,490
MARK HARTMAN: OK.

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00:04:06,490 --> 00:04:10,380
If we have no extra energy,
we're just a box of Shekibium--

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no, I wouldn't do that one.

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00:04:12,270 --> 00:04:14,020
That's very dangerous.

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00:04:14,020 --> 00:04:18,620
Everybody's electron is going to
be in the lowest energy level.

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So I want everybody
to stand on this line.

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Everybody.

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00:04:22,790 --> 00:04:24,670
You may have to squeeze.

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00:04:24,670 --> 00:04:25,432
All right.

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00:04:25,432 --> 00:04:26,910
AUDIENCE: Exsqueeze me.

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00:04:26,910 --> 00:04:28,360
MARK HARTMAN: OK.

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00:04:28,360 --> 00:04:32,020
Each one of you represents
an atom of Shekibium.

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00:04:32,020 --> 00:04:34,000
And what I'm going
to do is, I'm going

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to add energy to our box of
Shekibium. by shaking it up.

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Right?

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AUDIENCE: [INAUDIBLE]

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00:04:40,190 --> 00:04:41,470
MARK HARTMAN: That's fine.

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00:04:41,470 --> 00:04:43,386
I'm just going to call
it Shekibium, because I

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00:04:43,386 --> 00:04:44,770
imagine it's kind of different.

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00:04:44,770 --> 00:04:47,200
You'll notice, though,
that the energy levels here

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00:04:47,200 --> 00:04:48,490
are different.

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00:04:48,490 --> 00:04:50,330
It doesn't just go
one, two, three, four.

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00:04:50,330 --> 00:04:53,140
It goes one, three,
and then four.

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00:04:53,140 --> 00:04:56,350
Now, in the simulation
you can add energy

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00:04:56,350 --> 00:04:59,170
by shooting some
photons at you guys.

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00:04:59,170 --> 00:05:02,620
You can also add energy by
shaking it up, or heating it

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00:05:02,620 --> 00:05:03,400
up.

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00:05:03,400 --> 00:05:06,100
If you heat up, you guys are
going to bounce around more.

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00:05:06,100 --> 00:05:09,260
And if one atom bounces
into another one,

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00:05:09,260 --> 00:05:11,080
sometimes it can
knock the electron

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00:05:11,080 --> 00:05:13,070
into a higher energy level.

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00:05:13,070 --> 00:05:15,280
So I'm going to shake
all of you guys up,

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00:05:15,280 --> 00:05:19,270
and randomly you are going to
fill up some of these higher

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00:05:19,270 --> 00:05:19,885
energy levels.

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00:05:19,885 --> 00:05:21,520
Some of you can stay there.

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00:05:21,520 --> 00:05:22,930
Some of you will
get some energy,

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00:05:22,930 --> 00:05:24,555
and you'll jump up
to the higher level.

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00:05:24,555 --> 00:05:25,890
Ready?

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00:05:25,890 --> 00:05:29,545
Figure out which level you're
going to go to in your mind.

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00:05:29,545 --> 00:05:30,170
Can you see it?

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00:05:30,170 --> 00:05:30,794
Can you see it?

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00:05:30,794 --> 00:05:32,140
AUDIENCE: [LAUGHTER]

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00:05:32,140 --> 00:05:35,250
MARK HARTMAN: And shake them up.

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00:05:35,250 --> 00:05:36,711
OK.

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00:05:36,711 --> 00:05:37,210
OK.

137
00:05:37,210 --> 00:05:38,230
Oh, you dropped a yellow.

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00:05:38,230 --> 00:05:38,729
Oh!

139
00:05:38,729 --> 00:05:41,600
You crushed the yellow photon!

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00:05:41,600 --> 00:05:42,100
All right.

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00:05:42,100 --> 00:05:44,620
Now I stop.

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00:05:44,620 --> 00:05:48,370
And what I want
you guys to do is--

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00:05:48,370 --> 00:05:52,040
people-- Juan, are you in
between levels or what?

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00:05:52,040 --> 00:05:52,690
AUDIENCE: Yeah.

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00:05:52,690 --> 00:05:55,241
MARK HARTMAN: Let's have
you be up here at four.

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00:05:55,241 --> 00:05:57,740
Each one of you has been given
a different amount of energy.

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00:05:57,740 --> 00:05:59,440
You guys didn't gain any energy.

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00:05:59,440 --> 00:06:02,830
You guys gained some,
and so you go on up here.

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00:06:02,830 --> 00:06:06,220
You guys gained more,
and you went up here.

150
00:06:06,220 --> 00:06:11,317
Now, you all have
buckets of energy, right?

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00:06:11,317 --> 00:06:12,400
AUDIENCE: Delicious M&M's.

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00:06:12,400 --> 00:06:15,440
MARK HARTMAN: Delicious energy.

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00:06:15,440 --> 00:06:20,860
So it is your decision
now as an electron--

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00:06:20,860 --> 00:06:24,730
eventually, you are
going to drop back down.

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00:06:24,730 --> 00:06:27,880
Now, you can either drop back
down to the next level down,

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00:06:27,880 --> 00:06:30,430
or you could drop all
the way to the bottom.

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00:06:30,430 --> 00:06:35,980
But I want you to give out a
photon of the correct energy

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00:06:35,980 --> 00:06:38,530
if you drop a level.

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00:06:38,530 --> 00:06:41,740
Will you guys in the back be
able to give out any photons?

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00:06:41,740 --> 00:06:42,722
AUDIENCE: One.

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00:06:42,722 --> 00:06:44,680
MARK HARTMAN: No, because
they can't drop back.

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00:06:44,680 --> 00:06:46,760
They're already in
the ground state.

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00:06:46,760 --> 00:06:48,730
So Bianca, where
do you want to go?

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00:06:48,730 --> 00:06:50,060
You have to drop down.

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00:06:50,060 --> 00:06:50,822
AUDIENCE: There.

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00:06:50,822 --> 00:06:51,530
MARK HARTMAN: OK.

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00:06:51,530 --> 00:06:55,480
So what color of
photon, what energy--

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00:06:55,480 --> 00:06:56,260
oops.

169
00:06:56,260 --> 00:06:58,240
There are going to be
our colors in the model.

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00:06:58,240 --> 00:06:59,531
This is going to be our energy.

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00:07:03,020 --> 00:07:05,530
How much energy do you have
to give up to drop down

172
00:07:05,530 --> 00:07:07,510
to that lower level?

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00:07:07,510 --> 00:07:10,636
What energy level
are you at now?

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00:07:10,636 --> 00:07:13,320
AUDIENCE: Three.

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00:07:13,320 --> 00:07:14,820
MARK HARTMAN: Well,
you're at three.

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00:07:14,820 --> 00:07:17,630
How much energy do you have
to give up to get down there?

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00:07:17,630 --> 00:07:18,376
AUDIENCE: Two.

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00:07:18,376 --> 00:07:21,000
MARK HARTMAN: So what kind of a
photon do you have to give off?

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00:07:21,000 --> 00:07:23,100
AUDIENCE: Yellow.

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00:07:23,100 --> 00:07:24,060
MARK HARTMAN: Oh, nice.

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00:07:24,060 --> 00:07:24,560
OK.

182
00:07:24,560 --> 00:07:26,750
So Nikki, where
do you want to go?

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00:07:26,750 --> 00:07:28,530
AUDIENCE: Over there on three.

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00:07:28,530 --> 00:07:29,640
MARK HARTMAN: OK.

185
00:07:29,640 --> 00:07:31,740
So what color photon do
you have to give off?

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00:07:31,740 --> 00:07:32,622
AUDIENCE: Brown.

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00:07:32,622 --> 00:07:33,330
MARK HARTMAN: OK.

188
00:07:33,330 --> 00:07:34,980
Juan, where do you want to go?

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00:07:34,980 --> 00:07:36,320
AUDIENCE: I want to stay here.

190
00:07:36,320 --> 00:07:39,000
MARK HARTMAN: Oh,
that doesn't happen.

191
00:07:39,000 --> 00:07:41,020
You can stay here for a while.

192
00:07:41,020 --> 00:07:43,102
AUDIENCE: She drops
down to three, though.

193
00:07:43,102 --> 00:07:44,810
MARK HARTMAN: If you
drop down to three--

194
00:07:44,810 --> 00:07:45,380
what color?

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00:07:45,380 --> 00:07:46,274
AUDIENCE: Brown.

196
00:07:46,274 --> 00:07:47,168
AUDIENCE: [INAUDIBLE]

197
00:07:47,168 --> 00:07:48,510
AUDIENCE: Brown,
because I'm on three.

198
00:07:48,510 --> 00:07:49,676
AUDIENCE: Do I have to give?

199
00:07:49,676 --> 00:07:51,540
MARK HARTMAN: Yeah,
but you as an electron

200
00:07:51,540 --> 00:07:53,512
have how much energy right now?

201
00:07:53,512 --> 00:07:54,470
AUDIENCE: Four.

202
00:07:54,470 --> 00:07:56,220
MARK HARTMAN: But you
would have how much?

203
00:07:56,220 --> 00:07:57,882
Juan, you're standing
on our numbers.

204
00:07:57,882 --> 00:07:58,548
AUDIENCE: Three.

205
00:07:58,548 --> 00:07:59,579
I would give up red?

206
00:07:59,579 --> 00:08:01,620
MARK HARTMAN: So you have
to give up one electron

207
00:08:01,620 --> 00:08:04,500
volt. It's not that
you're giving off

208
00:08:04,500 --> 00:08:07,860
the energy of that level.

209
00:08:07,860 --> 00:08:12,030
You are just giving off the
energy of the difference

210
00:08:12,030 --> 00:08:13,260
between the levels.

211
00:08:13,260 --> 00:08:14,400
OK?

212
00:08:14,400 --> 00:08:16,027
So I shook you up.

213
00:08:16,027 --> 00:08:17,860
Now you can all decide
where you want to go.

214
00:08:17,860 --> 00:08:20,520
Juan, if you wanted to go
all the way back down to one,

215
00:08:20,520 --> 00:08:24,175
what energy would you give off?

216
00:08:24,175 --> 00:08:27,190
AUDIENCE: I would give
yellow, because I have--

217
00:08:27,190 --> 00:08:29,274
no, wait.

218
00:08:29,274 --> 00:08:31,440
MARK HARTMAN: How much
energy do you have right now?

219
00:08:31,440 --> 00:08:32,070
AUDIENCE: Four.

220
00:08:32,070 --> 00:08:33,903
MARK HARTMAN: Four
electron volts of energy.

221
00:08:33,903 --> 00:08:35,419
AUDIENCE: I would give brown.

222
00:08:35,419 --> 00:08:36,110
MARK HARTMAN: You
would give brown,

223
00:08:36,110 --> 00:08:37,857
because you're going
to go from four to one.

224
00:08:37,857 --> 00:08:38,270
AUDIENCE: Yeah.

225
00:08:38,270 --> 00:08:38,990
MARK HARTMAN: OK?

226
00:08:38,990 --> 00:08:42,289
So what we're going to do--

227
00:08:42,289 --> 00:08:44,870
well, no, we're not
going to do that yet.

228
00:08:44,870 --> 00:08:47,630
Can you guys come up
and be the collector?

229
00:08:47,630 --> 00:08:48,560
AUDIENCE: [INAUDIBLE]

230
00:08:48,560 --> 00:08:50,990
MARK HARTMAN: No, no, no, no.

231
00:08:50,990 --> 00:08:54,600
Now, everybody
change their level.

232
00:08:54,600 --> 00:08:58,250
Give us what you
need to give us.

233
00:08:58,250 --> 00:08:59,245
No, no, just one.

234
00:08:59,245 --> 00:09:00,745
You're going to
give off one photon.

235
00:09:04,560 --> 00:09:05,630
MARK HARTMAN: OK.

236
00:09:05,630 --> 00:09:06,199
All right.

237
00:09:06,199 --> 00:09:06,740
AUDIENCE: No!

238
00:09:06,740 --> 00:09:08,030
MARK HARTMAN: OK, we're ready.

239
00:09:08,030 --> 00:09:11,960
Now-- so everybody
fell down except Nikki.

240
00:09:11,960 --> 00:09:14,368
What do you have to do now?

241
00:09:14,368 --> 00:09:15,691
AUDIENCE: I can go down.

242
00:09:15,691 --> 00:09:17,690
MARK HARTMAN: She could
go down, but we're going

243
00:09:17,690 --> 00:09:21,106
to give the box another shake.

244
00:09:21,106 --> 00:09:23,480
And you guys get to choose
where you're going to jump to.

245
00:09:23,480 --> 00:09:24,320
AUDIENCE: [INAUDIBLE]

246
00:09:24,320 --> 00:09:24,680
MARK HARTMAN: No, no, no.

247
00:09:24,680 --> 00:09:26,960
We're just going to do
this element for now.

248
00:09:26,960 --> 00:09:29,060
Shake, shake, shake!

249
00:09:29,060 --> 00:09:30,980
Where do you want to go?

250
00:09:30,980 --> 00:09:33,921
Everybody should go up
at least one, right?

251
00:09:33,921 --> 00:09:34,420
There we go.

252
00:09:34,420 --> 00:09:35,150
All right.

253
00:09:35,150 --> 00:09:37,100
But you would have jumped up.

254
00:09:37,100 --> 00:09:40,460
Now we wait for a while.

255
00:09:40,460 --> 00:09:41,480
You're electrons.

256
00:09:41,480 --> 00:09:42,110
You're happy.

257
00:09:42,110 --> 00:09:44,250
You're in the high energy state.

258
00:09:44,250 --> 00:09:47,249
But now-- now think about where
you're going to jump down to.

259
00:09:47,249 --> 00:09:48,290
You've got two decisions.

260
00:09:48,290 --> 00:09:50,210
You can jump down one level,
or you can jump down two,

261
00:09:50,210 --> 00:09:51,084
if you're on the top.

262
00:09:51,084 --> 00:09:53,390
If you're on the middle,
you can only jump down one.

263
00:09:53,390 --> 00:09:54,050
Ready?

264
00:09:54,050 --> 00:09:55,740
And emit.

265
00:09:59,637 --> 00:10:00,345
MARK HARTMAN: OK?

266
00:10:00,345 --> 00:10:01,970
AUDIENCE: I know,
but [INAUDIBLE]

267
00:10:01,970 --> 00:10:02,720
AUDIENCE: Red one.

268
00:10:05,420 --> 00:10:06,810
MARK HARTMAN: So-- what?

269
00:10:06,810 --> 00:10:07,310
No.

270
00:10:07,310 --> 00:10:07,934
Where were you?

271
00:10:07,934 --> 00:10:09,257
You were on one.

272
00:10:09,257 --> 00:10:10,340
So you can't give off any.

273
00:10:10,340 --> 00:10:11,464
You're in the ground state.

274
00:10:11,464 --> 00:10:12,878
You have to stay there.

275
00:10:12,878 --> 00:10:16,920
AUDIENCE: [INAUDIBLE]

276
00:10:16,920 --> 00:10:18,770
MARK HARTMAN: OK.

277
00:10:18,770 --> 00:10:19,350
OK.

278
00:10:19,350 --> 00:10:19,880
You give--

279
00:10:19,880 --> 00:10:20,490
AUDIENCE: [INAUDIBLE]

280
00:10:20,490 --> 00:10:21,650
MARK HARTMAN: No, no, no.

281
00:10:21,650 --> 00:10:26,010
You only-- remember, though,
when you jump to the level,

282
00:10:26,010 --> 00:10:28,685
you only gave-- the photons
that were there only gave off--

283
00:10:28,685 --> 00:10:30,060
or, I'm sorry,
the electrons only

284
00:10:30,060 --> 00:10:31,800
give off one photon per jump.

285
00:10:31,800 --> 00:10:34,860
So I can't get three
photons from an electron.

286
00:10:34,860 --> 00:10:36,469
I have to get one photon.

287
00:10:36,469 --> 00:10:37,510
So where were you, Steve?

288
00:10:37,510 --> 00:10:38,010
AUDIENCE: Three.

289
00:10:38,010 --> 00:10:38,910
MARK HARTMAN: Three.

290
00:10:38,910 --> 00:10:41,100
And you're now going to one.

291
00:10:41,100 --> 00:10:44,153
So how much energy do
you have to give off?

292
00:10:44,153 --> 00:10:44,736
AUDIENCE: Red.

293
00:10:44,736 --> 00:10:46,510
One.

294
00:10:46,510 --> 00:10:48,063
MARK HARTMAN: So
from three to one--

295
00:10:48,063 --> 00:10:48,646
AUDIENCE: Two.

296
00:10:48,646 --> 00:10:50,430
AUDIENCE: Yellow.

297
00:10:50,430 --> 00:10:52,120
AUDIENCE: [INAUDIBLE]

298
00:10:52,120 --> 00:10:54,496
AUDIENCE: What's three
minus something equals one?

299
00:10:54,496 --> 00:10:57,530
MARK HARTMAN: You're going
back to one, but you have to--

300
00:10:57,530 --> 00:10:59,940
if you have an energy
of three electron volts

301
00:10:59,940 --> 00:11:04,020
to get back to one, you
have to give off two.

302
00:11:04,020 --> 00:11:06,480
So you have to give
us one yellow photon.

303
00:11:06,480 --> 00:11:08,080
One yellow, not the--

304
00:11:08,080 --> 00:11:08,580
there we go.

305
00:11:08,580 --> 00:11:09,860
All right.

306
00:11:09,860 --> 00:11:10,560
OK.

307
00:11:10,560 --> 00:11:13,050
Let's-- now, you guys haven't
dropped all the way back.

308
00:11:13,050 --> 00:11:13,940
That's OK.

309
00:11:13,940 --> 00:11:16,080
Now we're going to
shake the box again,

310
00:11:16,080 --> 00:11:19,620
and you guys get
excited, which means

311
00:11:19,620 --> 00:11:21,240
that you jump energy levels.

312
00:11:21,240 --> 00:11:22,200
We're going to inject--

313
00:11:22,200 --> 00:11:24,570
we're going to shake the box.

314
00:11:24,570 --> 00:11:25,320
Some of you go up.

315
00:11:25,320 --> 00:11:26,655
Some of you don't.

316
00:11:26,655 --> 00:11:27,870
AUDIENCE: I'll go to the top.

317
00:11:27,870 --> 00:11:29,070
MARK HARTMAN: All right.

318
00:11:29,070 --> 00:11:31,500
Now we wait for a
while, and you're

319
00:11:31,500 --> 00:11:34,256
going to give off some
photons as you jump back.

320
00:11:34,256 --> 00:11:36,160
AUDIENCE: Gamma photons!

321
00:11:36,160 --> 00:11:39,024
MARK HARTMAN: Can you give
off gamma ray photons?

322
00:11:39,024 --> 00:11:39,690
AUDIENCE: Can I?

323
00:11:39,690 --> 00:11:41,355
Of course I can!

324
00:11:41,355 --> 00:11:42,480
MARK HARTMAN: Are you sure?

325
00:11:42,480 --> 00:11:43,794
AUDIENCE: No.

326
00:11:43,794 --> 00:11:46,335
MARK HARTMAN: Where can you go
from here to give off photons?

327
00:11:54,620 --> 00:11:56,512
AUDIENCE: It's not fair.

328
00:11:56,512 --> 00:11:59,700
[INAUDIBLE]

329
00:11:59,700 --> 00:12:01,560
MARK HARTMAN: OK.

330
00:12:01,560 --> 00:12:04,320
So what I-- no.

331
00:12:04,320 --> 00:12:05,460
You don't want to give two.

332
00:12:05,460 --> 00:12:06,180
You only give one.

333
00:12:06,180 --> 00:12:06,990
AUDIENCE: He's out
of yellows, though.

334
00:12:06,990 --> 00:12:08,530
AUDIENCE: He's out
of yellow, so--

335
00:12:08,530 --> 00:12:08,960
AUDIENCE: Remember, we ran out--

336
00:12:08,960 --> 00:12:10,130
MARK HARTMAN: Oh, there we go.

337
00:12:10,130 --> 00:12:11,560
AUDIENCE: Yellow is what
we have the least of.

338
00:12:11,560 --> 00:12:11,890
MARK HARTMAN: OK.

339
00:12:11,890 --> 00:12:12,750
Yellow's what we
have the least of.

340
00:12:12,750 --> 00:12:13,260
All right.

341
00:12:13,260 --> 00:12:16,250
So what we've--

342
00:12:16,250 --> 00:12:17,190
OK.

343
00:12:17,190 --> 00:12:18,720
So at this point,
what we've done

344
00:12:18,720 --> 00:12:21,630
is-- if we add energy
to a box of gas,

345
00:12:21,630 --> 00:12:23,700
just like we did over
there with our hydrogen.

346
00:12:23,700 --> 00:12:25,990
We added electrical energy.

347
00:12:25,990 --> 00:12:27,630
We add the energy.

348
00:12:27,630 --> 00:12:31,050
We wait for the photons to
be given off by the atoms.

349
00:12:31,050 --> 00:12:32,260
All right?

350
00:12:32,260 --> 00:12:33,790
So what I want you guys to do--

351
00:12:33,790 --> 00:12:36,030
they're going to build
a spectrum of what

352
00:12:36,030 --> 00:12:39,060
you guys gave off.

353
00:12:39,060 --> 00:12:42,300
Now, each atom only gives
off one photon at a time,

354
00:12:42,300 --> 00:12:44,280
and you don't always
give off every photon.

355
00:12:44,280 --> 00:12:47,620
But if we had a box of you,
we'd get a bunch of photons.

356
00:12:47,620 --> 00:12:50,730
So I want everybody to
look at this spectrum.

357
00:12:50,730 --> 00:12:53,260
Again, this is intensity, or
number of photons we collected.

358
00:12:53,260 --> 00:12:55,710
AUDIENCE: We substituted-- no,
wait, there were two greens--

359
00:12:55,710 --> 00:12:56,585
MARK HARTMAN: I know.

360
00:12:56,585 --> 00:12:58,000
I moved them.

361
00:12:58,000 --> 00:12:58,920
It doesn't matter.

362
00:12:58,920 --> 00:12:59,800
It's just the-- OK.

363
00:12:59,800 --> 00:13:01,800
AUDIENCE: Mark, what
happened with [INAUDIBLE]??

364
00:13:01,800 --> 00:13:02,130
MARK HARTMAN: What's that?

365
00:13:02,130 --> 00:13:03,910
AUDIENCE: What happened
with [INAUDIBLE]??

366
00:13:03,910 --> 00:13:05,340
We have-- what's the name?

367
00:13:05,340 --> 00:13:06,410
Shekitians?

368
00:13:06,410 --> 00:13:07,210
MARK HARTMAN: Oh.

369
00:13:07,210 --> 00:13:09,430
Shekibium.

370
00:13:09,430 --> 00:13:11,910
Shekibium and Peterium.

371
00:13:11,910 --> 00:13:14,390
Well, he'll get to be
something next time.

372
00:13:14,390 --> 00:13:15,330
Yes.

373
00:13:15,330 --> 00:13:21,330
So why did we get photons
of 2.0 electron volts?

374
00:13:21,330 --> 00:13:22,700
Somebody explain why.

375
00:13:22,700 --> 00:13:24,960
AUDIENCE: Because of
the higher intensity.

376
00:13:24,960 --> 00:13:25,080
MARK HARTMAN: No.

377
00:13:25,080 --> 00:13:25,871
That's what we see.

378
00:13:25,871 --> 00:13:26,920
That's the observation.

379
00:13:26,920 --> 00:13:27,420
Right?

380
00:13:27,420 --> 00:13:28,540
We can observe.

381
00:13:28,540 --> 00:13:30,570
Juan, make an observation
about this spectrum.

382
00:13:30,570 --> 00:13:33,522
Intensity versus energy.

383
00:13:33,522 --> 00:13:34,480
Say what you just said.

384
00:13:34,480 --> 00:13:36,765
AUDIENCE: The yellow
has a high intensity.

385
00:13:36,765 --> 00:13:37,715
MARK HARTMAN: OK.

386
00:13:37,715 --> 00:13:40,860
So yellow-- ladies
and gentlemen.

387
00:13:40,860 --> 00:13:43,050
Yellow has a high intensity.

388
00:13:43,050 --> 00:13:46,140
Why, now-- let's think about
a model of light production.

389
00:13:46,140 --> 00:13:47,920
Why did we get 2.0?

390
00:13:47,920 --> 00:13:49,420
AUDIENCE: Because
we were changing--

391
00:13:49,420 --> 00:13:53,562
AUDIENCE: Because you
hadn't jumped [INAUDIBLE]

392
00:13:53,562 --> 00:13:56,820
I jumped back, so when I jumped
back, you had to give yellow.

393
00:13:56,820 --> 00:13:59,310
MARK HARTMAN: So when we
went from three back to one,

394
00:13:59,310 --> 00:14:01,860
the difference was two,
and we had to get that.

395
00:14:01,860 --> 00:14:06,064
Why do we have some
three and some one?

396
00:14:06,064 --> 00:14:08,845
AUDIENCE: [INAUDIBLE]

397
00:14:08,845 --> 00:14:11,220
MARK HARTMAN: So you had to
break from four to one, which

398
00:14:11,220 --> 00:14:12,402
gives us three, or--

399
00:14:12,402 --> 00:14:13,610
AUDIENCE: From four to three.

400
00:14:13,610 --> 00:14:14,985
MARK HARTMAN: From
four to three.

401
00:14:14,985 --> 00:14:17,850
We didn't have to always jump
back to the lowest level.

402
00:14:17,850 --> 00:14:18,690
OK.

403
00:14:18,690 --> 00:14:21,440
So let's look at this
spectrum over here.