05x04 - Rally Car, Small Spaces and Hammocks

[bunniefuu]

[Dallas off-screen] This
is the Science of Stupid.

Yes! This is the show that combines
serious science with severe stupidity.

Where we can enjoy a
multitude of mistakes...

And the only winners...

Are pain and shame.

Then we'll reveal
what went wrong.

And why with the assistance of
key scientific principles such

as inelastic collisions,
the conservation of angular

momentum, and
Newton's third law.

So get ready and
prepare for the pain.

Watch out...

It's the Science of Stupid .

In this show, we'll
be looking at...

The effects of friction...

Kinetic chains...

And mechanical work.

[man] [Bleep].

[Dallas off-screen]
But first, this.

Getting stuff from A to B is
just part of everyday life.

Carrying is good until
whatever you need to

carry becomes heavy.

So we humans invented the
wheel, then the wheelbarrow,

and then the lorry to carry
all those wheelbarrows.

[Dallas off-screen] Unloading
is actually a bit of an art.

Just ask these guys.

While the crates of
beer might be heavy,

they're still delicate.

So don't...

Yank them.

Just take your time.

You don't need to rush.

And remember, to unload
anything safely,

it has to get there
in the first place.

Unloading a trailer
seems simple.

But there's actually
serious science at work.

[Dallas off-screen] He starts
to tilt the trailer in order

to begin removing the load.

At first the load is held in
place by the static friction

between the rocks
and other rocks,

as well as the trailer itself.

Friction occurs at the
molecular level where the

rough edges of the
material interlock.

Once it reaches
the critical angle,

which is the point that it
overcomes static friction,

the load will begin to slide.

Once moving, the resistance
changes from static friction

to kinetic friction,
which is lower.

And the greater the angle,
the faster the load will move.

So whatever and wherever
you're unloading,

remember the
rules of friction.

Because it's not the sort
of thing you want to rub up

the wrong way.

[Dallas off-screen] Tipping
a large load is challenging.

So it's important that these
guys know their science.

You don't want it
to slide too fast,

so you need to increase
the angle gradually.

Perfect.

Well, perfect-ish.

[man off-screen] Oh.

[Dallas off-screen] The
large load slid unevenly.

This resulted in a lean which soon gave
us another critical angle.

And an awkward chat
with the foreman.

[man off-screen] Oh.

[Dallas off-screen] You need
the right equipment to deal

with a heavy load.

If you have to unload 600
bricks and the forklift is out

of order, then
don't use a digger.

Or you might unload them a little
quicker than you'd planned.

With just a chain
supporting the pallet,

there's little side
to side stability.

And when the bricks reach
the critical angle,

that plastic wrap isn't
strong enough to hold them.

Maybe this is why my
extension's taking so long.

Of course, some things are
easier to unload than others;

like a bike, when you
already have a ramp.

As long as you use it.

The only resistance you
get from wheels is rolling

resistance, which is lower
than both static friction

and kinetic friction.

But less resistance
requires more control.

So that doesn't happen.

Remember the driver's mantra:
your load is precious and must

arrive safe and sound...

Ooh!

Whatever it takes.

I'm a big fan of water slides.

After all, what better mix
could there be than sun,

cooling water and the
rush of adrenaline?

However, the emerging trend
of using inflatables on water

slides has me a tad concerned.

[Dallas off-screen] While
they might seem like fun,

they can also be problematic.

And this bloke is really
asking for trouble.

And he's found it.

Inflatables and water go
together like burger and fries

or milk and cookies.

They're a tasty combination.

But throw a slide into the mix
and you might end up feeling

a little queasy.

[Dallas off-screen] The water
flowing down the slide acts as

a lubricant to decrease
friction for riders.

Adding an inflatable
facilitates aquaplaning where,

on a microscopic level, the
slide and inflatable are not

actually in contact due to a thin film
of water between them.

The more submerged the
inflatable becomes,

the more drag it experiences,
and the slower it will move.

When traveling downhill,
gravity is likely to increase

its velocity.

And the inflatable can launch
off the slide with this

velocity before gravity
pulls it back down.

Basically, if you go fast
on a water slide without an

inflatable, you'll go
really fast with one.

But beware, if there's a
sudden change of direction and

your center of mass isn't
over your base of support,

the inflatable will capsize.

So let's see how the science
works in the real world.

[Dallas off-screen]
Look at these two go.

And keep on going.

The kid in the black tank top
doesn't have an inflatable,

so he faces higher drag
than the other two who do.

And less drag

means more velocity.

This looks like fun.

Just not for them.

As the inflatable reaches
the base of the slide,

it hits deeper water
and gets more submerged.

So the amount of drag it experiences
goes from a little bit

to quite a lot.

This dynamic duo seemed focused on
reaching new heights.

But at what cost?

Ah, dignity.

Their inflatable allows
them to aquaplane,

so they build up
a lot of velocity.

But when they hit the short
upward section of the slide,

that velocity is
redirected upwards,

launching them into the air

before gravity

can bring them down again.

So that's inflatables
on water slides.

Not the best idea.

Can you guess what science
this amateur stuntman is

about to demonstrate?

[Dallas off-screen] We asked
if you knew what science this

topless biker was
about to show us.

Did you guess
forwards momentum?

Our cyclist misses his ramp
and hits the railing with lots

of forwards momentum.

And because the railing is
lower than his center of mass,

that momentum flips him over.

But at least he was
dressed for the occasion.

I am a very competitive man.

It really doesn't matter
what the game; I want to win.

I often have my little niece
in tears before she's even

chosen her Monopoly token.

It's the way it should be.

All it takes to be
good is skill, focus,

and a symbiosis of
man and apparatus.

[Dallas off-screen] Skill.

Focus.

[man] Ah, that's my baby.

[Dallas off-screen]
And a symbiosis of man.

Oh, never mind.

To become the best at
something like, say,

arcade punch bags, you
need to know the skills.

Luckily, we're here to let
you in on the secrets with a

little help from our
old friend, science.

[Dallas off-screen] To punch,
he drives off with his back

leg and rotates
through his hips.

His arm's higher velocity
means a potentially greater

transfer of momentum, resulting in a
larger punching force.

These individual movements
working in sequence are called

a kinetic chain.

To absorb his momentum
after the punch,

he flexes his front leg and
pushes it into the ground.

Well, those are
some of the basics,

but let's not forget about the law of
conservation of momentum.

Which means that if
you miss the bag,

you'll keep moving forward.

I'd imagine that would look

a little embarrassing.

[Dallas off-screen]
Yup, it does.

That run up gave this guy
lots of forward momentum.

But as his aim is poor, none
of that was transferred to the

bag, and it's too much force for his
leading leg to absorb,

leaving this boxer
to take a dive.

[man] Come on, Mum.

[Dallas off-screen]
Good stance;

but has she remembered to
rotate her hips to give her

punch greater velocity?

Yes!

Hip rotation was good,
everything else,

less good.

Our pugilistic parent's poor
technique meant she followed

through with her body, but she
made another rookie mistake.

Never drop your guard.

So just drive with your back
leg and powerfully rotate your

hips to snap your arm forward,
and you'll be punching like a

champ in no time.

One, that's the
smallest of the numbers.

Here's a guy that looks like
he knows how to use his head.

I didn't mean that literally.

All right, settle down, class.

Eyes front and center, because it's time
for today's science lesson.

That part of the show where
we put one specific scientific

principle under our
microscopes and turn the

magnification up to 11.

So who can tell me what the
following have in common?

[Dallas off-screen]
This big bouncer.

This twisted fire starter.

[man] Oh my god!

[Dallas off-screen] And
this gym bunny's hop.

[man] Horton, going for a new PR.

[Dallas off-screen]
Personal record?

Ah, perforated rib cage.

Now, did you guess
chemical energy?

If so, then you can go straight to the
top of the class.

For the rest of
you, listen up,

as there'll be a
test afterwards.

[Dallas off-screen] This
corn chip is high in fat,

so it contains a lot
of chemical energy.

As it burns, it undergoes a
transformation that releases

surplus chemical energy
as heat, light, and sound.

This athlete's muscles are
using chemical energy from

food in order to
mechanical work.

And by using an
elastic material,

she's able to generate extra
energy and jump even higher.

As we all know, intense
exercise is hard to sustain.

And that's because it uses the
chemical energy that's stored

for immediate use
during short bursts.

Now, let's see who's
been paying attention.

Question one: Respiration
releases chemical energy

that's used in what way?

[man] Stratton, if you're
going you gotta commit, dude.

[Dallas off-screen] Looks
like Stratton here is gonna

use some of the stored
chemical energy in his body

to make some poor decisions.

[Stratton] You guys
didn't catch me.

[Dallas off-screen]
To make the jump,

Stratton needs to convert
chemical energy to mechanical

work using his muscles.

But he doesn't generate enough
of it to make the distance,

and hits the porch

with an impact force
equivalent to being hit by a

concrete block,

traveling at 50
miles an hour.

These two both seem incredibly
proficient at releasing

chemical energy.

I'm ready for
the big finish.

She wasn't, though!

Sprinting requires the release
of chemical energy stored

for immediate use.

This intensity can only be
sustained for short periods

before her muscles
need a rest.

Probably best not to
rest just there, though.

Question two: how can you
generate extra energy without

doing extra work yourself?

[man] You jumping, or what?

[Dallas off-screen] Ah, the old
trampoline into the pool trick.

This should be entertaining.

And it was!

But in a different
way than he planned.

Our gravity-defying grandpa
tries to use the elastic

energy of the trampoline to
gain energy and height without

more mechanical work.

But instead, he
got a lesson

in the law of gravity.

And now for our third
and final question.

Do fuels contain a little
or a lot of chemical energy?

[Dallas off-screen] Now, we
all know that fire needs to be

handled with care and respect.

It's essential to have a
responsible adult who knows

what they're doing.

[man] Go ahead.

Holy ****!

[Dallas off-screen]
So not him, then.

Fuels tend to contain
lots of chemical energy,

which was converted
into heat, light,

and sound by a
combustion reaction.

In this case, right
next to his feet.

[man] [Bleep]!

[Dallas off-screen] All
right, class dismissed.

[Dallas] If, like me, you have
the finely-tuned senses of an

apex predator, then you'll
know that when you're

temporarily deprived
of one of those senses,

for example getting
shampoo in your eyes,

then it can cause you
some difficulties.

[Dallas off-screen] It could affect your
awareness of surroundings.

It could affect
your judgement.

Or lead you to
overestimate your skills.

[man] I know where you are.

[Dallas off-screen] I'm
fairly sure you don't.

[man] Yah!

[Dallas off-screen] Well, it
was probably time to take

the tree down, anyway.

It is June.

It sounds obvious, but getting
around whilst blindfolded is

actually quite tricky.

You can't just put one
on and go about your day.

And science explains why.

[Dallas off-screen] Our man
moves about using visual clues

and proprioception via
receptors in his body.

These proprioceptors relay
information from his muscles,

tendons, and joints to his
brain and help him orientate

himself in relation
to his surroundings.

Without visual clues,
proprioception is inhibited,

and this makes it harder for
him to do complex tasks that

he hasn't previously tackled.

And easier for him to become
disorientated or lose balance.

So it is possible to navigate
the world whilst blindfolded.

But only by using
your other senses.

And it's best to familiarize
yourself with yourself

surroundings before
you put it on.

That way, you can anticipate
and avoid obstacles.

[Dallas off-screen] Let's see
if this little guy can show us

how to make it around the
lounge without visual clues.

[woman off-screen] Elijah.

[Dallas off-screen] Good, he's avoided
the door frame due to his knowledge of

his surroundings;
well played, sir.

[Elijah] Yeah, yah! Yah!

[Dallas off-screen] Still
probably best not to run.

Ah, a blindfolded juggler.

And it looks like he's getting
ready for the showstopper.

I suppose that's what they
call going out with a bang.

This circus performer is well
trained and initially can

perform the complex
task of juggling,

as years of practice help
him to anticipate where the

ba*ls will be.

But without visual clues, it's
easy to become disorientated.

And a small slip

leads to a painful hit.

This stunt rider
is a renegade.

He's decided to ditch the standard
helmet and go with a blindfold.

Which seems like a
questionable idea.

[man] This is not
going to end well.

[Dallas off-screen] That
wasn't altogether unexpected.

Amazingly, he managed to
get to the ramp without

hitting any obstacles.

But when his wheel slips,

he doesn't have any visual
clues to help him balance.

[woman] Is he OK?

[Dallas off-screen] I
imagine he's had better days.

I think that I'm pretty famous
for my cat-like reflexes.

In my defense, domestic cats
spend about two thirds of

their lives asleep.

Which might explain what's
going on with these guys.

[Dallas off-screen]
This home run slugger.

These students of dodgeball.

[man] This is such a
******* bad idea.

[man off-screen] Oh!

[Dallas off-screen]
And these guys.

[man] **** duck!

[man] Ah, 'cause of
the duck, is it?

[Dallas] When it comes
down to reaction time,

it seems many of our animal chums have
the edge over us humans.

Here's why.

[Dallas off-screen] Reaction
time is the time between a

sensory stimulus
and a response.

It's influenced by
multiple factors.

Like size.

A larger body will often slow
down reaction time as a bigger

animal will have
longer neural pathways,

and it has more
mass to accelerate.

Additionally, animals with
higher proportions of fast

twitch fibers in their muscles
will also have an advantage

when it comes to
faster reaction times.

So if you're small
and paying attention,

then you have a much better chance of
being able to react quickly.

[Dallas off-screen] Just
like Mr. Miaowgi here.

He's totally focused
on catching,

but less on landing.

[woman off-screen] Oh boy.

[Dallas off-screen] As this cat was so
focused on the stimuli in front of him,

he forgot about
his surroundings.

And ate the carpet.

White-tailed deer live on
a diet of vegetation, bugs,

twigs, and many shrubs.

None of which are in this
restaurant's salad bar.

Driven by lots of
fast-twitch muscle fibers,

some species, like this deer,
are natural sprinters and can

move quickly over
a short period.

Maybe it's all
venison on the menu.

This crocodilian is
smaller than that swimmer,

so it has shorter
neural pathways,

less mass to accelerate,
and should have a slightly

quicker reaction time.

But, to be fair, that
swimmer's pretty speedy too!

Cats, which their small mass
and fast-twitch muscle fibers,

should be able
to react quickly.

Bet you didn't
see that coming.

Okay, that's enough
scientific stupidity for now.

And, as always, don't try
anything you've seen at home.

And just in case you need it, here's a
little reminder of why.

[man] Because of
the duck, is it?