01x02 - Discus for Dummies

[bunniefuu]

RICHARD: Stand by.
It's the Science of Stupid.

[electricity crackling]

[alarm blares]

[reading]

...or you too will be going out
in a blaze of no glory.

Yes, this is the show that combines
science and stupidity.

Over the next half hour,
we present have-a-go heroes

meeting scientific concepts head-on.

We'll show you exactly
what went wrong and why,

by revealing the crucial
importance of torque,

- Newton's laws of motion...
- [b*llet ricochets]

...hemodynamics...

Oh, dear.

And combustion.

They've found out the hard way--

try to break the laws of science,
and they'll break you.

So don't try any of this stuff at home,

or anywhere else for that matter.

- [popping]
- Wake up!

It's the Science of Stupid.

- [electricity crackling]
- [glass shatters]

On this show, we'll see
what kinetic energy does

- to your bottom...
- [woman shrieks]

...what the ideal gas law
does to your car,

and what combustion can do to your garden.

But first, this.

- [glass shatters]
- [electricity crackling]

We all know that gyms are for people

who don't read enough books.

I go a lot, but there is
one item of gym equipment

that can be used for experiments
by the budding scientist,

the treadmill.

The fastest man on Earth,
a Mr. U Bolt, of Jamaica,

can run at over 27 miles per hour,

just not on this occasion
as the track is really short.

To give you an idea
of how fast Usain can run,

here's a treadmill going
at 24 miles per hour.

While a human's running speed is limited
by stride length and leg turnover,

if you want to break your own record,

the treadmill is the place to do it

as there's no wind resistance.

That's why these runners are achieving
such impressive speeds.

TRAINER: Nice work.

But let's face it, just running
on a treadmill is really boring.

Three cheers for inventive people
who want to push the boundaries.

First, let's look at getting
on a treadmill while it's moving.

Go on, soldier, charge!

[laughter]

In order to pull this off,
a runner has to accelerate rapidly

to match the speed of the belt,

but because the belt is so short,

there's very little time
before the feet are swept off.

Up above, inertia is keeping
the rest of the body motionless,

combine that with the belt
going backwards too fast,

and it will send him into a spin.

The solution is to start slowly,
then increase your speed,

or at least to hold on to the rails.

Simple. Well, I say that...

[man grunts]

Nice try.

Zero points.

And sorry for stating
the blindingly obvious,

but run in the right direction.

- WOMAN: ...go!
- [shrieks]

- RICHARD: It's important, yeah.
- [laughter]

One potential way to increase
your running speed is

to extend your stride length.

Let's see that in practice.

Okay, so that wasn't
the most scientific study,

it-- it was rubbish in fact.

Time for some proper experiments.

This guy's using a pogo stick.

Can the stored energy
in a compressed spring blast out

and give him that extra acceleration?

No.

What about a springy ball?

- No.
- [laughter]

And this guy's exploring friction,
the hard way.

Top marks for countering
the movement of the treadmill,

but by stopping that front wheel dead,

he feels the full force of the backward
movement of the belt.

[laughter]

- [electricity crackles]
- [metallic squeaks]

We think we know about spud g*ns--

good for annoying the cat,
but hardly a weapon for a grown-up.

Let's get serious.
Welcome to the world of potato cannons.

With a claimed muzzle velocity
of maybe 180 miles per hour,

and a supposed maximum range
of over 300 yards,

potato cannons can cause real damage.

Some backyard bazookas
can even punch through steel.

MAN: Oh!

So, if you thought the humble potato

was a harmless, starchy vegetable,
suitable only for frying,

boiling, and mashing,
think again, it's a*mo.

Hey, I'm Z Man.

Today, we're gonna test
this nuclear weapon.

[laughs maniacally, shouts]

RICHARD:
Firing potatoes into an empty field

can be seen as harmless fun,

but take aim at your friend's bottom,
from close range,

and it's a different story.

[screaming]

Do not try this yourself.

- [screams]
- [laughter]

[screams]

It blew a hole
in my long johns, as you can tell.

Yes, that's definitely
going to leave a mark.

Okay, bring on the science.

Your average potato cannon can teach us
about the ideal gas law.

When gases are heated,
they increase in volume,

but if a container prevents
that expansion of gas,

pressure builds up.

A standard potato cannon works by igniting
a propellant in a combustion chamber.

The potato in the barrel
is no match for all that pressure,

so the gas escapes rapidly
and propels the spud at great velocity.

[potato splats]

Simple and effective,
especially if smashing a window

and frightening the cat
is the desired objective.

To achieve this level of satisfaction,

the cannon maker relies
on avoiding some basic mistakes.

Mistake number one, sticking the cannon
together with duct tape.

[boy speaking Spanish]

[in English] Remember, a spud g*n
must handle rapid pressure changes,

that's what it does.

- [g*n blasts]
- [boy shrieks]

This one can't.

How many bazookas do you see
stuck together with duct tape?

There's a reason.

[laughter]

Mistake number two,
igniting without a base plate.

This is a school boy error.

- [flame whooshes]
- [laughter]

Mistake number three,
using a thin and flimsy base plate.

If the potato is tighter
than the base plate,

then your base plate
is gonna blow off like that.

Mistake number four, don't overdose
on the amount of propellant,

it's powerful stuff.

- [spraying]
- Okay, that's too much.

- Yeah... it was.
- MAN: Oh!

RICHARD: In fact, just a short squirt
will create a blast

that will always win
in the battle with the human hand.

- MAN: Oh!
- [laughter]

RICHARD: Mistake number five, don't forget
all that expanding, burning gas is--

well, it's expanding and it's burning.

[girl shrieks]

So don't put your finger
over the ignition hole.

MAN: ...your hand.

As you can see, this is completely burnt.

Anyway, it's a good time.

- But on the bright side, the cannon works.
- Okay.

RICHARD: Sensible choice
of target is, of course, vital.

No, I didn't mean-- Surely,
they're not going to... they-- they are.

- [man groans]
- And they did!

That wasn't a potato
but something much softer.

That's what you call a bull's-eye, yeah.

MAN: Yeah.

Oh, man.

[glass shatters]

RICHARD:
Can you guess what scientific concept

these overgrown kids
are about to demonstrate?

[scooter engine revs]

- [glass shatters]
- [electricity crackles]

These guys may be far too old
to be at the playground, but who cares?

Did you figure out what scientific concept
they're about to demonstrate?

Yes! It's inertia.

So when someone is
whizzing round in a circle,

his inertia resists this
constant change in direction,

and it feels like a force
is pushing him outwards,

and when he lets go,
he actually shoots off in a straight line.

[clattering]

- Like that!
- [laughter]

[clattering]

- [electricity crackling]
- [metallic squeak]

Roof jumping, where's the science in that,
I hear you say?

Find a roof and jump off.

What could possibly be
difficult about that?

[laughter]

- Oh!
- [laughter]

People who jump off roofs
can find out all too quickly

what an easy way it is to break something,

usually themselves.

Here's why.

When you jump, gravity accelerates
you towards the ground.

Doubling height increases velocity by 40%

and doubles the energy of the impact.

Land on your bottom from 15 feet,

and you'd decelerate so quickly,
you'd hit the ground

with an impact of over three tons.

To prevent serious damage,
you've got to decelerate

over as much distance as possible,

using something soft or collapsible.

It's why cars are designed
to crumple on impact.

Fifteen feet, three tons.

Remember those numbers.

The key to preventing broken bones
is never jumping off roofs.

The people in these clips
are ignoring this advice

and have chosen, instead,
to look for things to reduce

their rate of deceleration,
like water, for example.

For people lucky enough to have
a pool in their backyard,

jumping into it can seem like
a great way to break their fall.

Meet Snogs, he's got a lovely pool.

MAN: Come on, Snogs.

Don't think about it, you just gotta go.

[laughter]

RICHARD: As he hasn't taken a run up,

Snogs immediately demonstrates

the way gravity acts
on an object whatever its weight.

Although he hits the ground at much
the same speed as a lighter person,

because he's heavier,
he lands quite a bit harder.

Poor Snogs.

Okay, let's try again.

It's because there was horizontal distance
between him and the pool.

What if he had run before he jumped?

Well, ladies, show us what not to do.

[woman shrieks]

Perfect, thanks.

By adopting a sitting position,
she has absorbed some of the impact

through her gluteus maximus
but most of it went through her legs

so unfortunately, she broke both her feet.

Ouch.

No-one is taking their deceleration
experiments more seriously than this man.

Sometimes you have to go really high
to see how small you really are.

RICHARD: Will his ball be enough to absorb
the impact of his mass,

multiplied by his height off the ground,
multiplied by gravity?

Standby.

- Though, we'll never know.
- [man screaming]

Since he misses, that'll be about, what,

- three tons of force hitting the ground.
- [screaming continues]

Yeah...

- [man screaming]
- ...it was enough to break

to vertebrae in his back.

Sometimes, you don't have to go
that high to prove

how fragile your bones really are.

- [electricity crackles]
- [creaks]

They say it's not the g*n that kills,
it's the person holding it,

but that's not quite right,
technically, it's the b*llet.

Getting hit by a b*llet is bad news,

even if you're wearing
a military-grade, bulletproof vest

with extra protection plates,
like this dude.

So don't try this at home, I mean, really.

It's never a good idea to get into a place
where you might get shot,

but those who can't help it,
should wear one of these.

It's made of a nylon-like fiber,

that, by weight,
is five times stronger than steel.

This vest is flexible and easy to wear,

yet still strong enough to stop
most handgun rounds

from piercing the wearer's body.

When the b*llet hits the vest, it acts
like a spider's web catching a fly.

The energy of the impact spreads
in all directions along the fibers.

The b*llet loses energy and slows down.

Though the slug is slowed down
by the material in the vest,

it still packs a punch.

A nine-millimeter g*n round will deliver
over a ton of force to the wearer,

so even big blokes, like this guy,
are going to feel the impact.

Go.

RICHARD: Uh-oh. Are you sure?

- [g*n fires]
- [man grunts]

- MAN: Blaze 'em?
- All right, all right.

RICHARD:
This looks like a really bad idea.

Right, Neddie James. Right. Fire. Fire.

[man grunts]

RICHARD: While the vest may stop
the b*llet penetrating,

it can still leave a mark.

MAN: Whoa! God!

RICHARD:
His b*llet-resistant vest has done its job

- and slowed the b*llet down.
- [man groans]

His mistake was not realizing that vests
don't stop you getting hurt.

- [man groaning]
- MAN: All righty, take care.

I seen it!

RICHARD: That hurt because his vest
didn't have protection plates, like this.

In tests, b*ll*ts can leave a one
and three-quarter-inch dent in the target

and still be considered safe,
so a soft vest has its limitations.

[groans]

While it will stop
low-velocity b*ll*ts penetrating,

faster rounds tear through it
and leave potentially fatal injuries.

MAN: Live round, b*llet, nine-millimeter.

RICHARD:
This guy thinks he has the right idea.

He's wearing a vest
with a hard protection plate

because he's going to get shot
at point-blank range.

- [sh**ter shouts]
- [g*n fires]

[man screams]

His theory was crushed because
his friend hit him in the wrong place.

sh**ting him above the area of the vest

where the material was complemented
by the protection plate.

- MAN 1: Whoa, dude!
- MAN 2: Is that in you, man?

MAN 1: No, it ain't in him.

RICHARD: With a more powerful round,
that could have been a lot worse.

And with friends like that,
who needs enemies?

MAN 2: I guess
this concludes the documentary.

- [electricity crackles]
- [clatters]

Like folk music and mime artists,

unicyclists have their place,

usually, alongside folk music
and mime artists.

But since you're asking,
here's how it's done correctly.

A unicycle is basically an upside-down
pendulum and inherently unstable.

Staying upright needs
constant small corrections

to keep your center of gravity
above the pivot point

where the wheel touches the ground,
a bit like balancing a broom on your hand.

To accelerate forward, you have to shift
your center of gravity forward

while applying just
the right amount of force

on the pedals
to stop you hitting the deck.

There are few things
that make you feel less coordinated

than a unicyclist who can also juggle.

But take comfort in knowing
that getting to that stage

has involved a certain amount of pain.

- [crowd shrieks]
- [laughter]

[laughter]

Once you've cracked the basic cycling
on one wheel and grinning,

things get more interesting.

This is when the adventurous
unicyclist can explore

the boundaries of science,
often with dramatic results.

Like this guy throwing his center
of gravity around all over the place.

Awesome!

So where exactly is
that boundary of science, again?

[clattering]

Oh, here it is.

MAN: Okay, go.

RICHARD: Can you grind
a handrail on a unicycle?

No. No, you can't, but he can't, anyway.

MAN: Daddy's gonna follow you
in a just a minute.

RICHARD: Slacklining involves
lots of side-to-side motion

to counter the movement of the line,

something also virtually
impossible on a unicycle.

- There you go.
- [dog barks]

Jumping on a unicycle
is always going to be limited

by the fact that there are no handlebars.

Without them, placing the wheel precisely
where you want it is quite tricky.

And he certainly didn't want
to place it there.

[groans]

Now then, the trick
to getting the jump right

is holding onto the saddle,

but don't forget the pedals.

Yeah, that's both feet on them. Oh.

So assuming you could get up there,

is having a tall unicycle
easier than a short one?

This chap's gonna find out.

- [laughter]
- MAN: Yeah!

RICHARD: Science will tell you
that once you've lost your balance

on your tall unicycle, you have
to pedal fast to get it back again.

[laughter]

MAN:
Did you knock your tooth out?

RICHARD: Oh, the things people will do
to demonstrate the laws of science.

Thanks matey,
good luck with the dental work.

You enjoy that.

- [electricity crackles]
- [clattering]

The health and safety culture
may not have concerned

our cave-dwelling ancestors,

but if a person's
inner caveman drives them

to mix matches, dry timber,
and a few gallons of petrol,

it certainly should concern them.

Petrol on a bonfire?

MAN: It'll be fine.

RICHARD: Light a match?
What's the worst that could happen?

- MAN 1: Fire in the hole!
- MAN 2: Fire in the hole!

- [flames whoosh]
- [man yells]

RICHARD: That. Yeah, that.

- [laughter]
- MAN: Oh, my God!

RICHARD: Don't you just love the smell
of singed eyebrows in the morning?

MAN: Oh, my God!

Listen up.
You really mustn't slosh petrol around.

Here's why.

Weight for weight, petrol has six times
the energy of dynamite.

It evaporates quickly in air.

It's this invisible vapor cloud,
not the liquid, that's highly flammable.

That vapor is heavier than air
and evaporating all the time,

creating a vapor pool
that spreads out to the side,

getting bigger and bigger,

meaning its gases can still be
dangerously flammable yards away.

A mere 1.4% mix
of petrol in air is expl*sive.

The vapor might be invisible, but even
if you're not the brightest spark...

- [drum plays rim shot]
- Heh.

...you should still be able to smell it.

MAN:
Thirty-five dollars of gasoline.

RICHARD: Wow, that does seem a lot.

Might as well have been using
dynamite here.

- [flames whoosh]
- [man exclaims]

Never mind, that lawn
needed reseeding anyway.

Wonder how much fuel
they chucked on this one?

[booming]

Quite a lot, yeah.

MAN: Think you put a bit too much?

And another thing you need to know

about that gas vapor cloud,

it evaporates and spreads even faster
when the air is warmer.

So blazing sunshine
and an amateur pyrotechnician.

MAN: Big-[bleeps] bonfire, take one.

Now, kids,
don't try this at home. [laughs]

RICHARD: Well, it's not just kids,
no one should try this.

MAN: That's a big-[bleeps]
five gallons' worth, boys.

RICHARD: Five gallons, really?

Even half that would have
the same expl*sive potential

as 100 pounds of dynamite.

MAN: Initiation sequence, three, two...

RICHARD: Oh, I think
we know where this is heading.

MAN: ...one!

- [booming]
- [clattering]

MAN: [coughs] You okay?

RICHARD: So here's what happened.

Our friend here has made a great stack
in his boss's front yard.

but he uses way too much fuel,

then because the air temperature
is around 80 degrees Fahrenheit,

it's evaporated rapidly to form a huge,
flammable cloud, and it's all around him.

When the vapor cloud ignites,
it expands violently,

creating a whopping great bang
and giving him no chance.

Yeah, that is him getting fired.

No, really, he did lose his job over this.

- [electricity crackles]
- [clatters]

That's enough burning, bashing,
and brain ache for now.

Hope you were taking notes,
so if someone you know shouts,

"Oi, watch this!"

you'll be able to tell them
exactly which invincible law

they are about to collide with.

So until next time, be safe or we'll be
seeing you on the Science of Stupid.

[shrieks]

[groans]

[man shouts]