Name: Fan Request: Dave's Giant Exploding Balloon | Letterman
Uploaded: 2024-08-02T15:00:04.000Z
Description: Watch the stand-up comedy video 'Fan Request: Dave's Giant Exploding Balloon | Letterman' from Letterman on Comedy Buff. Published 2024-08-02. Transcript available.

Watch the stand-up comedy video 'Fan Request: Dave's Giant Exploding Balloon | Letterman' from Letterman on Comedy Buff. Published 2024-08-02. Transcript available.

here are the kids this is the future of america ladies gentlemen uh every so
often we like to
invite a few bright young students to demonstrate for us the latest scientific
principles that they
have learned it's something we call kid scientists and here they are hello kids
thank you so very much for being here kids first time in new york for everybody
no i've been here
before everybody been here before all right let's get right to the uh
scientific activities
and you uh my dear uh kareem nam am i pronouncing your name properly all right
kareem nice to see
you how old are you 12 years old 12 years old and uh are you in school yeah
yeah we're
we're already having fun aren't we uh where do you go to school i go to kennedy
junior high school
and i see that you're the it's the home of the some kind of hawk it looks like
a ferocious bird
there kennedy eagles eagles if i if i had just finished reading the shirt
all right kareem now you're going to be demonstrating something here that is
very
puzzling it's audio salt yeah audio salt all right kareem take it away here we
go
okay so first we're going to make this metal plate vibrate with this audio wave
driver okay and this
will create sounds of various frequencies and this will also set up two-dimensional
wave patterns
and this we're going to pour some salt onto this metal plate okay and the salt
that you will see
is going to vibrate except where there are nodal lines oh except where there
are nodal lines yeah okay so
so we're actually now seeing a sound waves uh visualized via the salt is that
correct yes okay now may i
touch it yes are you sure yes okay easy all right knock it off
you you you can use that one back at school all right let's go uh kareem you
need some help there
no i think it's fine it's fascinating because there are physics apply in every
aspect of natural
existence don't they it's just everywhere right yeah so i'm going i'm going to
turn it on and then when
it starts to go i'm going to ask you to put some more salt on oh sure as we go
along yeah
oh look at that those are the the nodule uh lines the place where the salts do
not move is the
places where the nodal lines nodal lines and that's where the waves cancel each
other out okay
can i get in here one more yeah whoa dump a little more on yes have you ever
tried it with fresh ground pepper
wow whoa oh my goodness look at that that's beautiful okay
kareem nam everyone beautiful job thank you very much
wow that was cool that was very cool wasn't it you uh georgia sturtz hi georgia
how are you good and
you go to lincoln junior high school you're in the eighth grade uh 14 years old
and that's home of
the lincoln lancers yeah uh eighth grade so you're getting ready to go to high
school oh yeah are you
excited about that definitely and where will you go to high school um naperville
central high school
that's very good i hear nothing but good things about it and uh a lot of your
friends going with
you to high school all of them all of them that's nice and you'll be soon
looking forward to maybe
starting to drive a little bit huh oh yeah yeah excited about that brothers and
sisters one older
brother one older sister and they're good everything's happy yeah do your folks
have a favorite of the three
and and and i gotta tell you your your teeth already look terrific and when
those when those things
come off they're going to be so beautiful you won't believe it thank you
my uh i was supposed to have braces when i was a kid but i i didn't my uh
parents uh use the money for a wet bar downstairs so
now this looks fascinating we're going to see
we're going to see a stream of light a stream of light all right take it away
whatever you need here
georgia okay well here we have a pop bottle filled with water and some
molecules of dye
now there's a hole on one end of the bottle but don't worry no water is going
to come out
because the cap is screwed on tight now i'm going to take this laser pointer
and i'm going to point
it through this side of the bottle so that it comes out the other end okay now
we shouldn't look
at the laser pointer okay don't look at the laser pointer yeah well you can you
can look at it but not
the we just can't shine it directly into your eyes yeah that's right yeah okay
all right i'm gonna need
all right i can see it on the monitor whoa wow wow that's exciting that that's
uh rebounding off
the molecules of color is that correct yeah that's called the tyndall effect
where you can it's bouncing
off the particles of the die wow yep so now i'm going to loosen this cap okay
so that some stream of
water comes out
that's the scary part's over oh that's what you think
okay what do we do here and we're gonna get this bucket first because water's
coming out can i unscrew
that for you um sure but first we're going to take the tape off because
otherwise oh there's the hole
in the thing there's what you're talking about all right now unscrew it just a
little bit a little
bit just to release a little pressure whoa wow you can see the stream of light
then you can actually
see it bouncing if you want to you can put your hand underneath it and see the
it actually on your
hand where the lights that's great comes right down there doesn't it now the
light is hitting the
water to air boundary and it's at an angle of reflection that is greater than
the critical angle
which causes it to be internally reflected now if the stream of water is not
too steep then it hits
it at the air interface which causes it to be totally reflected but as you see
the water level is going
down now if the water gets too steep because there's not enough water this rule
will be violated and you
will see the light on the wall because it's just shining right through that's
right no no water for it to
reflect into or beyond exactly it'll just straight go straight through as
though there were no water
because there won't be water that's fascinating
okay very nice thank you very much georgia georgia stir i'm sorry my hands are
wet beautiful job
nick rodmer hi nick how are you buddy welcome uh to the program good to have
you with us me too
uh you're uh uh seventh grade lincoln junior high and the lincoln we know those
are the uh lancers is
that right go to her school yeah you guys go to school together so your
classmates you know one
another sort of yeah okay um what are you going to do for us here nick well i'm
going to show you
how to um an example of volume expanding in a balloon here volume expanding in
a balloon yeah yeah you
ought to see my aunt hazel all right well if you want to come over here yes i
do uh nick i do want
to come over here well excuse me ladies well dave when a liquid changes from a
liquid to a gas
there's a very large volume increase so we're going to demonstrate this by you
pouring liquid nitrogen
into this funnel here but don't do it yet don't do it don't do it yet no no no
no now after you're
going after you pour the liquid nitrogen into the funnel you're going to take
this cap and you're
going to screw it on really tight but then you screw it on in the to the bottom
part of the funnel
or where do i screw it on yeah um you just uh you'll take the funnel out oh
take the oh i see okay
all right yeah but um and then you might want to take these gloves okay okay so
um and then once you
pull and uh you also might want to take these goggles
you can take these okay what about your buddies do they need the goggles too uh
no they can just
stand back stand back okay all right okay okay so now you can do i uncork this
yeah go ahead and
pour it in i uncork that uh yeah uncork that okay all right now just pour that
uh bottle into the funnel
all right the entire contents i think so well just as much as it
the whole thing i guess yeah you guess yeah yeah
that should that's enough there a little more a little bit more a little more
yeah you're supposed to put your goggles on get them on tell me when to stop
here uh about now okay
all right you know it dripped i felt it take the funnel take the funnel out and
cap it up yeah
now put the cap on okay and screw it on really really tight okay all right
there we go okay oh put on these ear protectors oh my god put these on what
what about you
just put them on put them on get back everybody get back get back get down
where are you get over here
get down get over there you might want to
get get down get down
this might take a while what this might take a while we're running out of tape
well if you want you can
take there's a needle up there you can i can't i have these things on you can
take them off for a
second that doesn't help me here when you do this you can take the needle over
there and poke it there's a needle on the table
right here all right poke it poke it
wow wow wow
wow okay man that was that was something wasn't it
is it safe to bring the audience back in
nick thank you very much kareem thank you very much georgia thank you very much
thank you very much there's your kid scientists everybody