Science Quiz

Q. How much do you
know about science
in a fantasy world?
by Mike Holthaus

Isn’t it a contradiction to mention
science and fantasy in a single breath . . .
or is it?

Even in a fantasy world, physical laws
govern the universe. Most D&D® and
AD&D™ campaigns I have been involved
with have taken the known (real) world
and added magick to it. This one change
makes a D&D world radically different
from the “real” world, but the addition of
magick does NOT cancel or CHANGE the
other laws of the universe. I have seen
DMs, on several occasions when players
point out inconsistencies in their refereeing,
say, “This is a fantasy. Anything
can happen!” However, this line of reasoning
generally does little to soothe an
angry player who has just lost his favorite
character. In the same way, it is very
irritating for a DM to have to explain a
simple physical law to a player who has
apparently forgotten that [water] runs
downhill — even in a fantasy world.

The following quiz will illustrate the
need to know a few of the laws of physics
and the need to be aware of a few of the
conditions likely to be encountered in an
[underground environment]. I have worked
as a [mining] engineer for 8 years
and been a player and DM for 7 of
those years. In that Time I have discovered
that many people are not familiar
with the principles expressed in these
questions and answers. There is no scoring
system for the quiz, since many of
the answers go beyond a simple “yes” or
“no” and can be expressed in many
ways. The important thing is to realize at
least why your answers are basically
correct or incorrect. These questions
may also inspire a few DMs with some
nasty ideas to spring on unsuspecting
players.

A. Take this quiz and see!

Malrob the Maroon, a wandering wizard,
is attacked and seized by a very
large roc. He is carried high into the air
before he manages to wiggle free of the
roc’s grasp. The DM informs Malrob,
“Well, you’re out of the frying pan and
into the fire, because you are now 3,000
feet in the air and dropping like a stone.”

1. Does Malrob throw his fly spell in
time? If not, why not?
2. If so, what is the result of this?

A mixed party of players encounters
an underground orc lair. The lair contains
large amounts of combustible materials
such as old wooden tools and
weapons, clothes, and jars of oil. After a
strategy conference the players decide
to throw several fireballs into the lair and
set [fire] to as much of the stuff as possible.
In the ensuing confusion, they will
charge the orc king’s throne to kill him
and his retainers. After the rest of the
orcs scatter in panic and confusion, party
members may loot what is left at their
leisure.

3. What is wrong with this plan?

You are with a party of players exploring
a dungeon. As you descend, you notice
that your torches, which normally
burn with a reddish-orange color, now
have a blue cap on their tips.

4. Should the characters ignore this
and press on, or should they consider
another course of action?

One player, after his character suffered
suffered through several gas explosions,
remembered hearing about canaries being
used by old-time miners to detect
dangerous gases. The next expedition
sets forth with birds in hand, confident
that they need not fear a gas explosion.

5. As the DM, should you curse the
players for spoiling your fun, or should
you chuckle silently to yourself?

A party of adventurers is exploring a
dungeon deep beneath a lake. As the
party enters a chamber, a heavy steel
door on the opposite wall starts to swing
open very slowly, and [water] is seen
spurting out from the edges. 5 ov the
6 members of the party are fighters, all
with 18 STR. Acting quickly, they <fighters can't have 18 STR!>
rush to hold the door and try to push it
shut. The 6th member, a magic-user,
urges them on but begins casting a water
breathing spell, just in case. At this POINT
the DM says, “You’re all as good as dead.
There is no way you can hold that door,
and water pressure will kill the magic-user
at this depth of over 1,000 feet.”

6. What would you, as a player, say?

Ragnor, a burly fighter, can lift 450
pounds. He spies a roughly sperical rock
about 2 feet across and decides to pick it
up and MOVE it.

7. Does Ragnor lift the rock, or does he
get a hernia trying?

Almost everyone will carry at least 50
feet of rope on an expedition.

8. How much does a half-inch-thick
rope, 50 feet long, weigh?

9. How much weight will it take to
break such a rope?

You are with a group of explorers deep
in a cave and you come upon a pile of
rubble where the roof has caved in. Most
of your party wants to turn back.

10. Should you turn back, or should
you not be overly concerned, and why?

Again, your party is in a dungeon AREA
where the roof above you looks ready to
fall in on your heads. A dwarf in your
group asks for a boost up. He strikes the
roof sharply with his war hammer and
feels it with his bare hand.

11. Does he know what he’s doing, or
is he just another crazy dwarf?

You are leading an expedition deep
into a dungeon and come upon a very
large room that has wooden posts holding
up what appears to be a very shaky
roof. Following your dwarf’s advice, you
press on regardless. In the middle of the
room, the DM rolls some dice, chuckles,
and informs you that the roof has caved
in suddenly, crushing the entire party.

12. As party leader, should you argue
vehemently with the DM, or rap the dwarf
player sharply about the head and shoulders
for his foolish advice?

A horse carrying a character fleeing
from a dragon gallops toward a chasm
30 feet wide. Not hesitating for a second,
the rider urges his mount to maintain full
speed and prepares to jump.

13. Are his chances good, bad or
indifferent?

Olias the thief comes upon a small
chest filled with neatly stacked gold
coins. The chest is 12” x 6” x 6”, and
Olias can carry 200 pounds.

14. Can he carry the chest and all its
contents?

A party leaving a small room with only
one entrance/exit triggers a trap that
drops a door into place, trapping a character
on the other side. Having no tools,
the rest of the party decides to return to
town for a magic-user with a passwall
spell. The room is a 10-foot cube, and the
party takes two days to return.

15. Will the trapped character be alive,
or dead of suffocation, when they get
back?

Olaf the Unbathed, taking a trip on a
sailing ship, watches an enormous whale
approach until it is about 120 yards
away. Figuring he can’t miss a target of
such great size, Olaf pulls out his trusty
spear and lets fly.

16. What are his chances of hitting the
whale at that distance?

Olaf’s ship later sinks, and he is forced
to shed his armor and tread water. The
DM tells Olaf he will roll dice every 6
hours to see if a ship passes.

17. How many chances should Olaf
get before he can tread no more?

Quiz
Answers

1&2: To find how far an object will fall
in a given period of time, use the formula
d = 16t2, where d = distance in feet and t = <check this>
time in seconds. In the AD&D™ rules, a
fly spell takes 3 segments, or 18 seconds,
to complete. So, Malrob would fall 5,184
feet before his spell takes effect, and he
doesn’t have that much room to spare.
No more Malrob, right? Well, yes, but . . .
because of air resistance Malrob will not
accelerate constantly and continually.
Terminal velocity for a falling body is
about 125 miles per hour, or 180 feet per
second. It takes a distance of 500 feet
and a time of 5.6 seconds to reach this
velocity. Therefore, after falling 500 feet
Malrob will drop at 180 feet per second
for 12.4 more seconds. Malrob will fall a
total of 2,732 feet: the first 500 feet plus
(12.4 x 180), or 2,232, more.

This leaves 268 feet to spare of the
original 2,500-foot height, and it appears
that Malrob is saved — but there is one
other fact to consider. Malrob is still
moving downward at 180 ft/sec and resembles
a plane pulling out of a steep
dive. A character using a fly spell has a
movement rate of 12”, which should be
halved if the flier is ascending (or attempting
to). If the DM gives Malrob the
benefit of every doubt, by not halving his
movement rate and by interpreting it as a
rate of 120 yards (outdoor scale) per
round, the maximum acceleration out of
his dive is 360ft/turn, which works out to
.6 ft/sec2. With this pitiful acceleration,
there is no way Malrob is going to pull
out of his dive. He will strike the ground
less than two seconds after he starts to
yell, “Fly!”
<G = 6.67 x 10-8 cm-3 gm-1 sec-2 >
<cf. Dragon #88: what is the error there?>

3: There may be several things wrong
with the players’ plan depending on other
circumstances, but the most glaring
mistake, and one almost always overlooked,
is the fact that a fire in an enclosed
area is very dangerous. In addition
to the danger of their characters being
burned by their own fire, the players
have forgotten two other things. The first
is that a fire will rapidly deplete the oxygen
in the cavern or dungeon, making
breathing difficult. The second is that
any fire produces carbon monoxide
(CO), a highly poisonous gas. On the
surface, in the open air, CO is unimportant;
underground, CO will almost certainty
kill every orc there, as well as all of
the characters. Carbon monoxide is odorless,
colorless and tasteless.

4: The players should run, not walk, to <REF2 link>
the nearest exit, for they are entering an
area containing methane, an explosive
gas. Methane is odorless, colorless and
tasteless. The only way to detect it is by
its blue flame, such as in a gas stove.

5: In this case, a little knowledge may
be a dangerous thing. Canaries have
been used in the past to detect carbon
monoxide, which is not an explosive gas.
Birds are much more susceptible to CO
than people, so an old miner would know
enough to beat a hasty retreat when his
canary keeled over. That works for CO
and other “tame” gases, but not for
gases such as methane. A canary will
know there’s too much methane in the
air when the players do: when it explodes.

6: The DM is half right. Water pressure
increases with depth. Water weighs about
60 pounds per cubic foot, so at 1,000 feet
of depth the pressure is 60,000 pounds
per square foot. A normal-sized (3’ x 6’)
door will have over l,000,000 pounds of
pressure on it, which means the fighters
don’t have a chance. The magic-user
might survive, though, if he can avoid
being crushed by the rush of water. The
Guinness Book of World Records says
that divers have worked as deep as 1,400
feet (“free swimming for short intervals”).
Whether a water breathing spell will provide
protection from “the bends” is a
matter of rules interpretation.

7: An average rock weighs about 150
pounds per cubic foot. A round rock 2
feet across has a volume of a little more
than 4 cubic feet (V=4/3 pir3). This rock
weighs over 600 pounds, and Ragnor will
soon be wearing a girdle.
<cf. How Heavy is My Giant?>

8 & 9: A manila rope ½” in diameter
and 50’ long weighs less than 4 pounds
and will hold more than 2,500 pounds
before breaking.

10: A roof that has caved in is actually
safer than one that has not, in many
cases. This is because loose rock has
already fallen away, and also because
the roof tends to form a natural arch
when it caves in.

11: The dwarf is probably an old miner;
as are most dwarves. Rock that is
loose and ready to fall will sound hollow
when struck sharply and will also vibrate
slightly. This is not easy to detect, so
only give this ability to a character who
has had experience in mines.

12: Once again, the dwarf is correct.
Wooden posts will not fail without a
great deal of popping and cracking. This
will almost always give enough warning
to beat a hasty retreat.

13: According to the Guinness Book
of World Records, the official distance
record for a long jump by a horse and
rider is just over 27 feet, so the horse
would have to be pretty great to even
have a shot at it. A paladin’s mount
would have the best chance, but those
steeds are generally intelligent and probably
would not try such a stupid stunt. Be
sure to take into account extra weight,
such as plate armor or gold, that is being
carried.

14: A 12” x 6” x 6” chest contains 432
cubic inches. Stacked coins fill about
75% of this space, or 324 cubic inches.
Gold weighs 1,200 pounds per cubic
foot, so the coins alone weigh 225
pounds. The thief will have to leave some
gold behind. <cf. How Many Coins in a Coffer?>

15: A man uses about 1 cubic yard, or
25 cubic feet, of air each hour under
normal conditions. The room is 1,000
cubic feet in volume, containing enough
air for 40 hours of normal breathing. After
this much time, the oxygen is depleted
to the point where the character is
unconscious. The character would remain
unconscious for as much as another
40 hours, depending on his constitution.
Therefore, after 48 hours the character
will be unconscious but definitely
alive. Physical activity, even of a mild
sort, can increase oxygen intake up to 12
times over the normal rate.
<cf. Air Supply, Duration>

16: The world’s record in the javelin is
“only” 317 feet, 4 inches, so Olaf’s spear
will very likely fall short even if he has a
strength of 18, because he can’t take a
running start like a javelin thrower.

17: The world’s record for treading
water is a little more than 72 hours; this is
only a bit more than 12 rolls’ worth of
time, and what are the chances of a ship
coming near enough for crew members
to spot Olaf in the water? One in 20? One
in 100? One in 1,000? Go ahead and give
Olaf a “lucky” 13th roll anyway, and be
sure to mention what a nice guy you are
just before that last roll.

OUT ON A LIMB

‘Gone too far’

Dear Editor:
With regard to the article about science in a
fantasy world in DRAGON #60: While I do
agree that all of Mr. Holthaus’ examples are
correct and just, I think he has gone too far.
Water running downhill is one thing, but calculating
the water pressure on a “normal” door
is something quite different, especially in a
world where gods, demons, and ultra-powerful
magic take a hand in everyday affairs.

What actually happens as Malrob casts his
Fly spell? Does the magic slow his descent as
it builds up power, but give him control only
after the spell is completed?

As for the CO and methane questions, any
self-respecting dwarf or gnome should know
of these dangers and how to handle them.
After all, they are “miners of great skill.”

Ragnor has an intelligence of 3 if he’s going
to try to lift a spherical rock, which could be
rolled.

The weight (encumbrance) of 50 feet of
rope is listed in Appendix O of the DMG as 75
gp. Breaking a rope requires more than 2,500
Ibs. or 25,000 gp of pressure — sufficient to
hold anyone’s trust, but one must take into
account the position, age, and condition of
the rope before ruling that a rope has broken.

The ceiling questions are good, but again I
would trust the dwarf to use his mining abilities
(and the DM’s fairness) to help the party
overcome these slight problems.

Any horse would instinctively shy away
from a chasm it could not jump.

The best way to figure out if a person could
carry something is to have him or her try. Any
good DM would know the weight of the item
and be able to compare it to the player’s
strength. This is easier than figuring the volume
and density and all the equations that Mr.
Holthaus uses.

Olaf must look up the range of his spear in
the Players Handbook, where it is established
as 30 yards — considerably shorter than the
desired 120 yards.

Mr. Holthaus has brains and knows how to
use them. But I don’t think such rigorous application
of physical and mathematical laws
belongs in the D&D and AD&D games. I am a
chemistry major and I have a good knowledge
of the laws of nature. As a DM, I must remember
that not everyone has had the same
education I have, so to be fair to the players I
must “play dumb.” Common sense, not science,
must play the key role.

Roger Reinsmith
Detroit, Mich
(Dragon #62)