- Welcome to orientation, Vault Dweller.
In today's lesson, we'll be going over defending yourself
in a world after complete nuclear annihilation.
You might need to vaporize some people or things,
so let's make sure that you at least know the science
of what's going on.
(upbeat electronic music)
So, Vault Dweller,
I'm sorry, I can't talk like that anymore.
So, Vault Dweller,
I'm sure that you're eager to get back out there
into the Wasteland,
and to vaporize some raiders
as you see right there,
But we should at least have some kind of understanding
of the physics of the laser and energy weapons
in "Fallout" before we do so.
First, what does "vaporization" really mean?
There's a big difference between separating all the atoms
in a person's body and reducing them to a pile of ash.
First of all, atomic bonds are really hard to break.
Consider a water molecule with one oxygen atom
and two hydrogen atoms.
To break the bonds between the oxygen and hydrogen
of just 18 grams of water,
you would need to input
920 kilojoules
of energy, or about the same amount of energy
in the form of work that it takes to stop
a small car speeding down the highway
at 60 miles an hour,
or the amount of energy that comes from blowing up
half a pound of TNT.
If energy weapons were separating all the atoms
in a person's or supermutant's body,
then it would take a gargantuan amount of energy,
3,000,000,000 joules of it.
That's the same amount of energy you'd have to input
to melt 5,000 pounds of steel or power armor.
But let's dig into that number a little bit like a mole rat
to see where it comes from,
because most of the energy that goes into vaporizing someone
is spent vaporizing that person's water.
A pile of ash is devoid of water content,
so energy weapons must at least be vaporizing all of that.
If the average person is, maybe, 70% water
and weighs 78 kilograms,
then, on the whole, the average person contains
56 kilograms of water.
That's what we have to vaporize.
Time for a chemistry lesson.
Thinking back to the water molecule again,
we have to break both of its oxygen-hydrogen bonds
to totally vaporize it,
and to do that, we have to insert what's called
the "bond enthalpy" energy, which is the amount of energy
you need to insert into a chemical bond to break it.
And we know that the oxygen-hydrogen bonds
break by inserting 460 kilojoules of energy per mole
of these bonds.
A "mole" is a standard measurement
defined as the number of atoms in 12 grams of pure carbon,
12 which just happen to be
6.02x10
to the 23rd atoms,
now known as "Avogadro's constant,"
named after the scientist who discovered this constant.
Now, using this as a standard measurement,
if you take the combined atomic mass of an atom
or a molecule like water and add it up,
that's how many grams of this stuff
are in 6.02x10 to the 23rd of that stuff.
Since hydrogen has an atomic mass of roughly one,
and oxygen has an atomic mass of roughly 16,
that means that the water molecule
has a combined atomic mass
of 18,
yeah (laughs).
So, that means that in every
6.02x10 to the 23rd water molecules,
there are 18 grams of water.
Now, with all that chemistry out of the way,
how much energy does it take to vaporize someone
like in "Fallout?"
If the average human body contains 56 kilograms of water,
we divide this by 18 grams of water
per one mole of water to find the moles,
which equals a little over
3,000 moles of water.
And in every one of these
3,000 moles of water,
there are two oxygen-hydrogen bonds,
remember back to the water molecule,
which means there are roughly 6,000 moles
of these oxygen-hydrogen bonds,
which, remember have a bond enthalpy energy
of 460 kilojoules per mole.
You see where we're going with this.
So, if you multiply these values out,
6,000 moles
times 460 kilojoules
per mole,
you get a gargantuan amount of energy;
2.8 billion joules
of energy,
which is like (lightning crashes) two full lightning bolts.
(cash register dings)
So, there you have it, Vault Dweller!
With "Fallout's" energy weapons,
you're literally carrying around lightning in a bottle,
or microfusion cell, ready to vaporize raiders.
The technology may have changed, but war,
war never changes, except...
Wait, no, it totally changes.
Think of the difference between dropping one guy,
dropping a nuclear bomb on a city,
and a bunch of dudes lining up on a hill, 10 feet away,
and shooting each other.
Yeah, yeah, war totally changes,
because science.
Okay, bye!
(upbeat electronic music)
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or suggestions for future episodes,
you can hit me up on the comment section below.
Thanks!