Suma
  • Member for 10 years, 11 months
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Can bullets fired into the air kill a person when they fall?
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96 votes

As for physics, it is really very simple, the kinetic energy is converted to a potential energy while climbing and then to kinetic again when falling, with some of it converted to a heat due to ...

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Can a computer be hacked to use a connected speaker as a microphone?
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52 votes

Most speakers really can work as microphones; the signal is weak, but it is there. See, for example, All speakers are microphones: What happens is that in a speaker there's a magnet and coil, and a ...

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Has anyone innocent ever been arrested because of contraband that was planted in their luggage?
41 votes

A Slovak citizen was (without his knowledge) planted a detonation device in his luggage as a part of airport security test. The device was not found at the airport and the person was arrested later in ...

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Are personal electronics a risk to commercial aviation?
39 votes

Cell phones present a separate category, as they actively and intentionally transmit (i.e. generate E-M field), while the other appliances produce only a E-M noise, which is a lot weaker, see Small ...

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Can flatworms learn a maze by digesting other flatworms?
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36 votes

No, they cannot. They were experiments done which indicated the possibility, but the results were never reproduced, therefore it is most likely their setup was somehow wrong. Moreover, no mechanism ...

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Are Fair Trade products guaranteed to be 'fairer'?
24 votes

Very little of the extra the end customer pays goes actually to the primary producer. While the fair trade goods cost usually substantially more than competitive products (often +50-100 %), the price ...

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Are United States scientists building a Stanford Torus space station in the Ukraine?
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24 votes

There are no traces anywhere of a Stanford torus being built by NASA, and such undertaking is highly unlikely. However, what was built in cooperation between NASA and Ukraine in the Yuzhmash in 2011 ...

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Shouldn't tell about pregnancy in first trimester
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18 votes

Yes, the first trimester is the most risky one, as American on Pregnancy Association on miscarriage tell us: Most miscarriages occur during the first 13 weeks of pregnancy. Studies reveal that ...

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Has the Catholic Church ever retracted an "ex cathedra" statement?
16 votes

No clear case known Some statement X was made, intended to be infallible Later, 1) evidence has shown X to be false or 2) X was retracted/reformulated/revised by a subsequent statement, illustrating ...

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Ultrasound pest control devices
16 votes

Not effective against mosquitoes: Electronic Mosquito Repellents Don't Work, Say Researchers Study investigators had counted mosquitoes landing on bare body parts — mostly arms, legs and feet — ...

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Does grass alone produce enough oxygen for life?
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14 votes

Plants are oxygen neutral The question wording is a bit misleading, as – surprise – plants do not produce oxygen, when you consider their whole life cycle, including their decomposition. They produce ...

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Is DRM effective?
13 votes

Short answer: We do not know for sure, but it is likely for most products some DRM is better than none. Long answer: There were no controlled experiments done which would reliably answer this. The ...

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Was Einstein a poor student?
12 votes

Einstein online mentions Einstein had some problems passing an exam so that he can start Polytechnical Institute studies at earlier age then normally allowed, but his problems were limited to ...

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Are ion heaters significantly more efficient then normal electric heaters?
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10 votes

TLDR: No, it is not more than 100 % efficient, the test performed was probably invalidated by using a heat meter assuming water as a heat transfer fluid, while propylene glycol/water mixture was ...

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Does chamomile help you to relax?
10 votes

The chamomille used as herb at least in Central Europe is German chamomile (Matricaria recutita, also known as Matricaria chamomilla). About its medicinal effects following is said on Wikipedia: A ...

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Did the the crew of Flight 1549 (that ditched in the Hudson) do an exceptionally good job?
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9 votes

In Ditching Myths Torpedoed! you can find analysis of 179 ditches from NTSB Records, years 1985-1990 and 1994-1996: Myth 1: Most Ditchings Aren't Survivable If you believe this, you've been led ...

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Can an electronic device reduce scale buildup in waterworks?
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8 votes

I have met with a similar device in a form of either permanent magnet or an electro-magnet. In both cases the devices failed when subject to an experiment: Scientific and engineering studies ...

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Does Instagram withhold likes to increase usage?
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5 votes

There is an article dealing with this subject: Is Instagram Strategically Withholding My Likes? The Instagram representative denies this: On Twitter, Instagram’s CTO and co-founder Mike Krieger ...

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Does painting your radiators black make your heating more efficient?
4 votes

Motto They are white by convention, and they heat by convection. Analysis I am sorry this answer is mostly theoretical, however I was unable to find any practical material in this area so far. The ...

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Is Robinson Crusoe the first English novel?
3 votes

For English you can find a list of multiple first novels, which mentions the definition problem: There are multiple candidates for first novel in English partly because of ignorance of earlier ...

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Can the human eye distinguish frame rates above 60 Hz?
3 votes

The human eye is not able to distinguish between 60 Hz and 100 Hz when only watching (even less could suffice provided the image is prepared correctly, as evidenced by movies projected at 24 Hz in the ...

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Anaesthesia awareness: fact or myth?
3 votes

About how frequently Anesthesia awareness happens, Wikipedia tells us: Awareness occurs in 20,000–40,000 patients out of the 20 million US surgeries performed each year (between 0.1% and 0.2%)1 when ...

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