01x12 - Jet Pack Failure

[bunniefuu]

RICHARD:
This is the Science of Stupid.

- [electricity crackling]
- [glass shatters]

[alarm blares]

[reading]

These are misguided explorers
lost in a world without science

with only blind bravery to guide them.

We'll see the science
that could have saved them...

while we marvel
at the principles of flight...

and the miracle of traction...

as the scientifically impaired
rub up against friction...

and pump up the pressure.

Proving that only the universe
and human stupidity are truly infinite.

And that without science, there's no limit
to what can go horribly wrong.

- [laughter]
- [bleep]

Break out the first aid kit...

[glass shatters]

...it's the Science of Stupid.

- [electricity crackling]
- [glass shattering]

[grunting]

On this show, we'll see
the after effects of Hooke's law...

[man screams]

...and how you can increase
your brain power.

But first, this.

[glass shatters]

[electricity crackling]

A gentle breeze on a hot, summer afternoon
can be enormously refreshing,

but sometimes,
if the wind is strong enough,

it can have devastating effects.

MAN: Oh, no! Oh!

Holy [bleep]!

- RICHARD: Language.
- [bleep]

And it's not just cars,
maybe he's into fly fishing.

Unfortunately, wind can occur
when you least expect it.

MAN: Whoa...
WOMAN: Did it get somebody?

MAN: Yeah, it clobbered them.

MAN 1: This is the most dangerous thing
I've ever seen.

RICHARD: Really? I would say this is.

MAN: We're in a tornado.

We are in the tornado.

RICHARD: I can't hear you.

MAN: We are in the tornado!

RICHARD: You're in a what?

MAN: We are in the tor...

RICHARD: Well, what are you doing there?

The fastest wind speed
ever measured inside a tornado

was just over 300 miles an hour,

so it's quite evident
how potent Mother Nature can be.

Despite these warnings, people have still
decided to harness that energy

and use the wind
for recreational purposes,

such as kite flying.

So, if you don't want your kids to fly,
you'd better listen to the science.

Wind is caused by the uneven heating
of the Earth's surface by the sun.

As the heated air rises
and cold air rushes in to replace it,

wind is created.

And it's this movement
that you can use to fly a kite.

When flying, dig your feet into the ground
and lean back.

The smaller the angle
between the flyer and the ground,

the less likely you are to be pulled over
in a strong wind.

Done correctly,
you'll be a master of the sky.

Done incorrectly...

the wind will propel you into the sky
and then into the ground.

He looks like a big, strong lad,
and he's trying to lean back.

Oh, now he isn't. He's stopped.

[laughter]

Kite flying is so deadly,
it's been banned in Pakistan.

She's not in Pakistan,

but probably should be banned
from kite flying.

MAN: Yeah, watch this Hayley,
he's going to [bleep] it right up.

RICHARD: Have a little faith
in your friends.

Oh, then again...

[woman laughing]

OK, so what went wrong?

He starts well, leaning back,
but when that wind becomes too strong,

he should run with the kite while
still leaning back, not lean forward.

[woman laughing]

At least he left an impression.

WOMAN: Look what he left...

[laughter]

- [electricity crackling]
- [creaks]

There's nothing quite like
an open expanse of water in front of you

and a couple of hundred horsepower
behind you.

The wind in your hair,
salt in your nostrils...

and the steering wheel in your face.

So, boat owners, if you want
your day on the water

- to be plain sailing...
- [comedic cymbal crash]

...pay attention to the science.

Boats use the water's buoyancy
to support them,

but traveling through the water
creates drag and slows you down.

The way to avoid this drag
is to get enough power

to propel you across the surface
of the water instead.

This is called planing.

The boat now comes into contact
with the water less and can go faster.

But as the front of the boat lifts,
more air can get underneath,

increasing instability.

So, is putting a NASCAR style V-8 engine

into a 13-foot aluminum boat

and racing it at speeds of up to


Yeah.

Jet sprint boats,
capable of such tight turns

that the driver and navigator
can experience

a whopping seven G's every few seconds.

With forces like that at play,
lightning-fast reactions are a must.

- [crash]
- [crowd screaming]

Especially for the spectators.

Now, if you've got plenty of money
and even larger white fronts,

you can take it to the next level
with a hydroplane.

But before you do,
remember this little fact.

For every 10% increase in speed,
there's a 20% increase in lift.

So, in seconds, the boat turns
from a hydroplane into an airplane.

This guy knows his stuff.

The hull's touching the water with an area
about the size of a handkerchief,

reducing drag and increasing speed.

But has he thought this through?

Minimal water contact
also reduces stability.

At least there's nothing to bump into.

Uh, except that. Yeah.

Maybe he wants to go into advertising?

Well, he just did.

With 3,000 horsepower, this hydroplane
is barely touching the water.

What can go wrong?

Oh, yeah. That.

These 6,000-pound hydroplanes
are the heavyweights of water sports,

covering the space
of a football field in a second.

But, remember,
the less you touch the water,

the more susceptible you are to this.

COMMENTATOR: The boat's broken in half.

RICHARD: However fancy the boat,
the physics remain the same.

The moral of the story,

if you can afford a powerboat,
take care at speed.

[electricity crackling]

[metallic thud]

[metallic squeak]

OK, ladies and gentlemen,
it's competition time.

What scientific principle is this brave,
young physicist about to experience?

- [glass shatters]
- [electricity crackling]

Who managed to peek into the fate
of this plucky physicist?

MAN:
This is a see-saw nut shot.

RICHARD: He's using
the principle of the lever.

[man screams]

You put weight on one side
and get force out the other,

so you really don't want
to be standing there

unless you want to re-enact
Tchaikovsky's famous ballet,

The Nutcracker.

According to a recent scientific study,

someone who's practiced juggling
for just six weeks

increases the wiring
in parts of their brain

responsible for hand/eye coordination
by almost five percent.

But if they're so clever, why would they
want to do something like this?

[shouts indistinctly]

But to be honest,
extreme juggling acts like that

are best left
to highly trained professionals.

Because when amateurs
try to imitate the experts,

things have a tendency to go wrong...

and keep going wrong.

To help people like him,
here's some science.

In essence, juggling comes down
to simple projectile motion

with each ball following a neat,
parabolic arc.

Move your hands
in a rough figure-of-eight motion,

your right hand moves clockwise,
and your left hand moves counter clockwise

with alternating tosses.

The ba*ls in the air are being
pulled back down by gravity.

If you double the height you throw them,

they'll be falling 40% faster
by the time you catch them.

Newton's second law means
the faster an object falls,

the more impact force
it generates when it lands.

Once you've mastered
your figure of eights,

there's no limit
to what you can juggle with,

though I'd strongly advise against
trying this.

Yeah.

Oh, yeah!

RICHARD: Wonder what happened
to his other fingers?

It's also worth noting
that any change in direction in your toss,

even if it's just one or two degrees,
can cause deviations of nearly a foot.

And you should bear this in mind,
especially when you're playing with fire.

[crowd gasps]

Oh, come on.
Have you forgotten already?

Throwing the clubs higher

means they'll be traveling faster
when they fall.

WOMAN: Are you OK?

RICHARD: No, his head hurts.

- [electricity crackling]
- [metallic squeak]

In 1955, the Western world
got its first glimpse

of what would become bungee jumping

when a National Geographic expedition
to Vanuatu

happened upon a group of local daredevils
leaping from a wooden tower

with a length of vine
attached to their ankles.

Since then, bungee jumping
has become a worldwide phenomenon.

Some bungees are made up
of over 1,000 strands of elastic,

allowing jumpers to dive
from death-defying heights and survive.

The current record is over 1,000 feet.

That's the height of the Eiffel Tower.

Bungee jumping is also attractive
to practical jokers.

Stop messing around
and pay attention to the science.

- [man 1 laughing]
- [man 2 sighing in pain]

Bungee cords
are essentially springs.

Hooke's law explains that
the greater the force applied

to the bungee cord,
the longer it stretches.

This stretching builds up elastic energy
in the cord, creating the bounce.

But too much force, like extra weight,

and they'll overcome
the elastic limit of the rope.

And an understanding of that elasticity
is especially important

when jumping off a 360-foot bridge.

MAN: Oh! [bleep]

RICHARD: Amazingly,
this girl wasn't seriously hurt,

but has ditched the extreme sports

and taken up
collecting porcelain frogs instead.

That was an extreme demonstration

of how the elastic limit
of a bungee cord works.

But you don't always need
to go to such lengths.

Because the same rules apply

whether you're jumping off a bridge
or going horizontal.

The problem with
running on the ground

is you'll never generate
enough momentum for a good stretch.

And if you are going to conduct
an experiment like this...

I'd avoid taping your arms down.

It looks like a vertical fall is by far
the best way to get a good stretch.

But, remember, bungee cords
are bespoke bits of kit,

so any cost-cutting exercises
using homemade bungee

can only end in disaster.

This is the ultimate bridge wedgie.

RICHARD:
Underpants elastic co --could work.

[man screams]

MAN: Ohh! Ohh!

RICHARD: But only if he'd used
it in the rope, not the harness.

[man screaming]

I wouldn't want to do
his laundry.

[screaming continues]

Hang about.
How's he gonna get down?

[screaming continues]

Oh, I see.

- [glass shatters]
- [electricity crackling]

To stay upright
or walk on two legs,

the human body
has a mind-blowingly complex system

of mechanics and neuromuscular control.

Just look what a well-balanced body
and a healthy mind can do...

in heels, for whatever reason.

- Ta-da!
- RICHARD: Well done.

In fact, the human body
is an inherently unstable system.

[woman screams]

[laughter]

Especially when you add alcohol.

Y'all watch, this is how
ya get on a saddle.

RICHARD: Yeah, we're watching.

Grab a hold of the saddle horn,

you put your leg over...

- [man screams]
- [clattering]

Not content with over two million years
of human evolution,

some have decided to use their hands
instead of feet for support.

And in most cases, that's a bad idea.

Hands are clearly not meant for walking.

But if you do plan to turn the world
on its head,

pay attention to some science.

A perfect handstand
needs to adhere to two simple rules.

Number one, you'll need strength,

each arm will have to take a load
of around 80 pounds for the average man.

And, secondly, you'll need balance.

Your center of mass is around your navel,

so you'll want to keep it directly
above your base of support,

in this case your wrists,
to avoid toppling over.

To save you from any embarrassments,

why not start practicing
in the privacy of your bedroom?

But don't forget,
a perfect handstand requires strength.

How much strength?

[dog panting]

More than that.

Nothing to see here. Move along.

When you're more confident,
you can progress to your living room.

It's probably worth remembering
that falling on your head

from a height of one meter
carries a 50% chance of serious injury.

Maybe she wants to be on the telly.

But if a stable chair isn't up to scratch,
what about an office chair?

Oh. Let's rewind.

At this point, his center of mass
is too far forward

for the chair to remain stable.

Yeah, don't do that!

But some people aren't satisfied
with just doing a handstand.

They want to walk, as well.

This is a highly trained gymnast.

Not only does he have
extraordinary balance,

but has bags of upper body strength,

allowing him to move
from one hand to the next.

As with the static handstand,

he makes sure his weight is distributed
evenly in front and behind his wrists.

This isn't a highly trained gymnast,

he hasn't got bags of upper body strength,
and he hasn't got extraordinary balance.

In fact, I don't think
he's a gymnast at all.

- [electricity crackling]
- [metallic squeak]

In 1771, a French bloke
called Nicolas-Joseph Cugnot

is said to have invented and built
the world's first automobile,

which he then drove into a wall.

So I suppose he also invented
the car crash.

And despite leaps and bounds
in road-safety technology,

we're still crashing today, especially
when the temperature drops below zero.

When roads are icy, the best advice
I can give is... don't drive.

Why?

Because when driving on ice,

you're at least ten times
more likely to be injured.

- MAN: Easy! Easy!
- RICHARD: See?

And it's not just cars
you need to worry about.

[man laughs]

So, if you want to avoid being
another accident statistic this winter,

pay attention to some science,
accompanied by some happy music.

It isn't the ice that's the problem,
it's the water that sits on top of it.

In cold weather, a very thin layer

reduces the friction
between the road and the wheels.

Sending too much power to the wheels

means you'll overcome the tire's
adhesion limit and your wheels will spin.

That lack of friction
also makes steering very difficult,

so a sharp turn like this
is almost impossible.

Instead, your actual path
will be more like this.

And it's the same with braking
as insufficient friction

means you'll keep moving forwards
until something else stops you.

And one friendly piece of advice,

before you begin
experimenting with friction,

check the thickness of the ice.

With the ice checked,
it's time to begin driving.

MAN: Sorry!

RICHARD: Done correctly with no excessive
acceleration or braking,

friction, and therefore traction,
is maintained,

and you'll move
more safely across the ice.

Done incorrectly,
and the excessive revving

means you'll always have
an uphill struggle.

Or downhill. Just a struggle, really.

And with hardly any friction
between the tires and the ice,

any traction will be overcome by gravity,

meaning a road this icy
should never be attempted...

even on foot.

WOMAN: Are you all right?

RICHARD: Once you manage
to get on the open road,

approach bends with caution.

And remember, stopping's also a problem
when there's no friction.

Sometimes it's easier to understand
scientific principles

by going back to basics
and using simple apparatus.

And sometimes it's not.

So, let's recap.

Snowy conditions create a layer of water
between the tires and the road,

decreasing friction and making it
difficult to steer and stop.

OK, so, shall we see that
in action again?

Here's a normal suburban road,
transformed into a scene from Swan Lake

but with fewer tutus.

Well, I'm assuming.
I can't actually see the drivers.

So, make sure when steering,

turning...

or just coming to a stop,

that you always have enough friction
to overcome your inertia.

Otherwise, the scene from Swan Lake
turns into a scene from car-maggedon.

- [glass shatters]
- [electricity crackling]

So that's enough pratfalls
into the world of pain.

Please don't try any of this at home.

But if you do, it's worth having
the local hospital on speed dial.

[lively fiddle music playing]

[man screaming]

[crowd screaming]