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PROFESSOR: And then I
want them to explain why.

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Why did our result
come out this way?

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Who would like to
take a shot at it?

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Who'd like to take
a positive risk?

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Steve?

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OK, come on up.

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So first tell us
about your prediction,

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and then tell us how
it was different.

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AUDIENCE: After
[INAUDIBLE] it would be red

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and do not have a difference
in flux according to position.

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It should be the
same flux everywhere.

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I predict that this space where
the red lights in the spectrum

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lets the light spectrum
that creates all that.

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So you got a spectrum,
you're going to move this,

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but it's still there,
so this [INAUDIBLE]

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in this light spectrum.

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PROFESSOR: OK, so
Steve's prediction

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is similar to a lot
of our predictions.

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Some people said that the
whole thing would be red

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and it would be the same flux.

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It would be the same amount of
light that was getting through.

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Some people said that the
red would be a high flux,

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but then as we went to the
other colors they'd still be red

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but they would maybe
be a lower flux

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because the filter was going
to block some of that light.

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Asith, were you
volunteering for something?

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You want to explain your
model, or your prediction,

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and then what actually happened?

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AUDIENCE: My predication
was that just

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like the exit sign over there
that red will sink through.

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But as the color went on I
thought some of the colors

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will sink out, so they'd
be a bit lighter here.

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But when I saw this, the
whole thing was just black,

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but it had a bit of
lighter color here.

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That's the only difference
between my prediction.

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PROFESSOR: OK, so how would you
create an explanation for why

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we do see this, because
I think a lot of people

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had the same idea.

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Why is it that
we're seeing this?

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Why are we only seeing
the red band go through?

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AUDIENCE: If you, for example,
if you guys take the red filter

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again and look at the exit sign
and take another blue filter

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and look at the exit sign,
you wouldn't see the red color

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sink through the blue
filter, but you'll see

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it sink through the red filter.

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Same way here.

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Since the color red is here,
it wouldn't let the blue color

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sink through.

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It's the exact opposite of
what the blue filter did when

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we looked at the exit sign.

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PROFESSOR: OK, I like that.

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I like what Asith did.

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He connected what we
saw with the exit sign.

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The red filter let through the
red light from the exit sign,

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but not anything else.

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Remember when we looked at
the green and the blue paper,

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it had low flux.

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There wasn't a whole lot
of light coming through.