Join 3,561 readers in helping fund MetaFilter (Hide)


Testing your materials science expertise
January 18, 2011 12:39 PM   Subscribe

Are any of these materials science analogies ambiguous? How can they be improved?

For a upcoming event in my academic department, I've come up with a list of materials science analogies to use to quiz my (graduate and faculty) colleagues. The test is meant to be similar to one of Hoeflin's IQ tests, but very subject-specific. To avoid arguments, I'd like to throw out any questions that are ambiguous, and keep only the ones with a single obvious answer that comes to mind without using reference materials. Some may be esoteric, though. What do you think?

(E-mail me if you'd like the complete answer list.)

I'd first give them these examples:

Example:
LIGHT : PHOTON :: HEAT :
Answer:
PHONON. The PHOTON is the quantum unit of LIGHT; the PHONON is the quantum unit of lattice vibrations, or HEAT.

Example:
PLASTIC : HARD :: ELASTIC :
Answer:
STIFF. A HARD material resists PLASTIC, or permanent, deformation; a STIFF material resists ELASTIC, or reversible, deformation.

The quiz:

1. CONTRAST MICROSCOPY : NOMARSKI :: CRYSTAL PULLING : ?
2. ARPANET : ADVANCED RESEARCH PROJECTS AGENCY :: NITINOL : ?
3. 2 : SADI :: 3 : ?
4. J/M^3 : ENERGY DENSITY :: PA-M^(1/2) : ?
5. LOCATION : NONUNIFORM :: DIRECTION : ?
6. AU-AL BOND PADS : PURPLE PLAGUE :: NAPOLEON'S ARMY'S BUTTONS : ?
7. >1 : HEAT CAPACITY RATIO : >-1 BUT <1/2 : ?
8. COVER WITH SI : SILANIZE :: CROSSLINK WITH S : ?
9. CRYSTAL : GRAIN :: MAGNET : ?
10. SALT AND WATER : EUTECTIC:: OIL AND WATER : ?
11. OPAQUE : ADIABATIC :: TRANSPARENT : ?
12. IRON TO MAGNETITE : FIREARMS :: HYDROXYAPATITE TO FLUOROAPATITE : ?
13. PIANO KEYS : EBONY - IVORY :: HF ACID CONTAINER : ?
14. BUBBLE GAS THROUGH : SPARGE :: FLAKE OFF : ?
15. SHOCKLEY AND BRATTAIN : BARDEEN :: COOPER AND SCHRIEFFER : ?
posted by Mapes to Science & Nature (13 answers total) 2 users marked this as a favorite
 
For what it's worth, I have a Physics Ph.D. and I only know two of these: #9 ("domain", right?) and #15 (cute.)

That said, is a phonon really a quantum of heat? "Heat", for me, means some thermal distribution of modes. I would have said "lattice vibration" for that one.
posted by Johnny Assay at 1:01 PM on January 18, 2011


The popular story of the decay of Napoleon's army's tin buttons during his Russian campaign is highly questionable at best. Short version of the counterarguments: tin pest affects only relatively pure tin and the buttons were not pure enough to be affected; even if they were, the rate of decay would not be fast enough to have the claimed effect.
posted by DevilsAdvocate at 1:20 PM on January 18, 2011


(Unless that's what you were going for; I know next to nothing about Au-Al bond pads, so if purple plague is a highly-questionable-at-best explanation for the decay of those, ignore my objection.)
posted by DevilsAdvocate at 1:23 PM on January 18, 2011


I'm with Johnny Assay on all points.

Except I also know 8: vulcanize (right?)
posted by gijsvs at 1:31 PM on January 18, 2011


PLASTIC : HARD :: ELASTIC :

Thinking about the material (a hard plastic vs a soft elastic rubber) rather than the property, I'd have answered SOFT, but then I'm just a chemist.

1. Czochralski --- seems ok to me.
2. Nickel Titanium Naval Ordnance Laboratory --- this one's pretty obscure
3. Nernst, perhaps? ---- I'd have said Clausius instead of Sadi.
4. (fracture) tougness --- fairly stright forward
5. Vectorial? --- seems vague
6. tin pest --- dodgy though.
7. ?
8. Vulcanize --- an easy one
9. Domain --- again pretty basic
10. emulsion? dispersion? colloid?---- I'm not clear on what you mean here. Salt and water don't form azeotropes the way alcohol and water almost automatically do.
11. Diabatic? --- But then I started life as a quantum chemist.
12. ?
13. ? really don't know what you're going for here.
14. ? don't know the specific word here.
15. BCS --- nice one.
posted by bonehead at 1:32 PM on January 18, 2011


I might have gotten as many as 6 (czochralski, nickel titanium,domain,teeth,polyethylene,exfoliate). Maybe fewer.

I think the light:photon one was ambiguous. Maybe warmth:phonon, as warmth is a characteristic of matter, but heat can be interpreted as radiation.

I thought the one on guns was a little obtuse, and I think some of them were obtuse
in the same way, involving as they did specific and disparate applications of materials
science in widely dispersed fields.
posted by the Real Dan at 1:33 PM on January 18, 2011


Assuming the intended answer to #8 is "vulcanize," that's a bit iffy. Covering anything with silicon would be silanization, but vulcanization is specific to rubber and similar materials. Proteins can be crosslinked with S as well (via their cysteine residues) but that's not called vulcanization. (OTOH, the processes can be distinguished in that vulcanization involves the addition of sulfur, while crosslinking of protein occurs with sulfur that is already incorporated into the protein.)
posted by DevilsAdvocate at 1:34 PM on January 18, 2011


5. Vectorial? --- seems vague

I believe the answer to #5 is anisotropic. (A property that varies by location is nonuniform; a property that varies by direction is anisotropic.)
posted by DevilsAdvocate at 1:51 PM on January 18, 2011


13. ? really don't know what you're going for here.

Piano keys used to be made of ebony and ivory (but aren't any more, at least not ivory); hydrofluoric acid containers used to by made of _______ but aren't anymore. (Don't know what the answer is, though.)
posted by DevilsAdvocate at 2:00 PM on January 18, 2011


Is 10 spinodal?

This quiz seems very much of the "guess what I'm thinking" or "aha answer" sort: even if there's not much ambiguity in the final answer, you might still run into people complaining about them being a bit far fetched. That's a pretty reasonable thing to do, though, if you want to wind people up a bit or stimulate some discussion!
posted by doop at 2:22 PM on January 18, 2011


#5, that's obvious now that I see it.

#13, In the modern day HF is transported and stored in HDPE. They used to be various kinds of metal, if I recall correctly (which I probably do not).
posted by bonehead at 2:28 PM on January 18, 2011


Spinodal decomposition is the precess, perhaps, though the analogy with the eutectic would be to the triple point, would it not?
posted by bonehead at 2:37 PM on January 18, 2011


"Correct" so far (inasmuch as they match what I was thinking):

1. Czochralski (associated person)
2. Naval Ordnance Laboratory (acronym)
3. (Nernst is close :) )
4. Fracture toughness (characteristic units)
5. Anisotropic (DevilsAdvocate has it: direction vs. location)
6. Tin pest
7.
8. Vulcanize
9. Domain (smallest characteristic unit)
10.
11. Diabatic (was thinking diathermal, but equally good)
12. Teeth (surface hardening reactions)
13. DevilsAdvocate's thought process is right on; think hyphenated
14.
15. Bardeen (Nobel prizes)

Thank you very much for the conditions/caveats/warnings so far. I'd much rather hear these now than later, and I'm likely to throw out at least a few of these and also change the examples.
posted by Mapes at 3:10 PM on January 18, 2011


« Older Looking for words (a phrase, a...   |  Chinese or Kanji translation: ... Newer »
This thread is closed to new comments.