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Questions tagged [technology]

67 questions
30
votes
6 answers

Canonical everyday-life example of a technology that could not work without humans mastering QM in analogy to the application of GR in GPS?

The GPS is a very handy example in explaining to a broad audience why it is useful for humanity to know the laws of general relativity. It nicely bridges the abstract theory with daily life technologies! I'd like to know an analogous example of a…
c.p.
  • 1,564
29
votes
3 answers

Is there any current technology that depends upon a deep understanding of quarks?

I think the title about says it all. If someone asks me "What good is the Theory of General Relativity?" (or what did Einstein do that was so great, or whatever) My pat answer is, "You use GPS right? Well, GPS requires knowing the location (in…
John
  • 413
20
votes
6 answers

Are human eyes the best possible camera?

I am not a physiologist, but whatever little I know about human eyes always makes me wonder by its details of optical subtleties. A question always comes to mind. Are human eyes the best possible optical instrument evolved by natural selection? Is…
user1355
17
votes
5 answers

Why do dental drills need such high rpm?

Dental drills have always been cutting edge technology when it comes to high rotational speeds. According to Wikipedia modern drills reach more than 180 000 rotations per minute (rpm), which is 3000 rotations per second! For comparison, household…
A. P.
  • 3,408
16
votes
3 answers

How Earth communicates with Voyager I?

After taking a basic signals & systems class and learning about the frequency domain, I started wondering: How the heck do scientists still communicate with Voyagers I and II??   Do they send/receive signals in a frequency that is otherwise…
user541686
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14
votes
3 answers

Why and how will we be able to image extraterrestrial planets in the next two decades?

According to a recently published article, a well-established Cambridge astrophysicist stated that: the “origin of life, where it exists, and whether aliens exist, is going to be crucial over the next four decades”. He added: “We know now that…
ixtmixilix
  • 494
12
votes
2 answers

Can a compass be used in a submarine?

This question is motivated by several "myths" I have heard recently - I want to know if there is a problem with using a compass inside a submarine. I can see two different issues, so I'm wondering if anyone can clarify (if you do some googling on…
levitopher
  • 5,419
11
votes
2 answers

What causes this strange noise in a pair of walkie-talkies?

Let us suppose that Bob and Alice both have walkie-talkies. They are both 3m apart from one another. Alice pushes her walkie-talkie to speak but instead of speaking, she starts walking toward Bob. Both Alice's and Bob's walkie talkies are facing…
JW Feynman.
  • 143
11
votes
4 answers

Space Elevator on Mars with Today's Technology Possible?

I know it's not possible with Earth today, but With today's level of material science technology, would it be possible to make cable strong and light enough to make a space elevator system connecting a Mars-synchronous satellite to an anchor on…
mring
  • 931
9
votes
2 answers

Which is the "roundest man-made object": Gravity probe B rotor or the Avogadro project sphere?

The Avogadro project is part of the efforts to replace the artefact-based standard kilogram with a definition based on naturally reproducible objects. The main challenge is to make a very precise sphere of isotopicaly pure silicon. There are…
Slaviks
  • 4,493
7
votes
4 answers

How do aerospace engineers choose a landing system? (Curiosity rover)

The Sojourner rover with the Mars Pathfinder used a entry, descent, and landing system involving airbags to land on Mars. The Spirit and Opportunity rovers each used more-or-less the same system involving airbags to land on Mars. The Curiosity rover…
David Cary
  • 1,063
6
votes
4 answers

Existing (possibly everyday) technologies that must account for electromagnetic momentum?

Can anyone suggest existing technologies that must account for electromagnetic momentum? I believe one example to be confinement in nuclear fusion; but momentum there appears in an averaged form, as pressure. Just to give an idea of what I mean with…
pglpm
  • 4,109
5
votes
1 answer

What piece of technology is able to record the exact phase of microwaves?

I read that in VLBI, the signals of microwaves are recorded and then later combined. A famous example of this is the Event Horizon Telescope which imaged the black hole. Presumably, the telescopes recorded the phase of the microwaves. This tells me…
MaximusIdeal
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5
votes
4 answers

Are quantum mechanics calculations useful for engineering?

I heard it's is pretty tough to get results for more than a few quantum particles. Are quantum mechanical calculations useful at all for any technology that is being sold? Or do they use quasi-classical results at most? Is there hope that advances…
Gere
  • 1,527
5
votes
1 answer

What type of solar energy technology has the most future potential?

In terms of dollars per watt, using theoretical efficiency limits, what technology holds the most promise to become the primary solar energy capture technology? My hunch is carbon-based modules, since materials are abundant and relatively easy to…
induvidyul
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