140 votes
Accepted

Does Electromagnetic Hypersensitivity (EHS) exist?

Electromagnetic hypersensitivity is believed to be an example of a nocebo. A nocebo is a reverse placebo - one's negative expectations cause harm. EMF exposure hasn't been able to cause symptoms in ...
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  • 8,517
113 votes
Accepted

Do consumer computers include components that can connect to the internet when the computer is apparently turned off?

Yes, most modern computer processors include hardware with the capability to fully control all components of the computer (regardless of the power state of the system as a whole), to access all data ...
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  • 1,687
25 votes
Accepted

Does turning the lamp in my classroom off and on use more energy than it being turned on for 30 minutes?

This page at Cambridge University says its a myth. There is a burst of energy when you turn them on, but its equivalent to 2 seconds of run time. Also the light lifetime is not seriously affected by ...
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  • 15.7k
22 votes

Does Electromagnetic Hypersensitivity (EHS) exist?

Yes there are people that believe they have the problem but it does not come from physical exposure from electric fields. It is usually classified as Psychogenic pain, also called psychalgia and can ...
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  • 320
17 votes
Accepted

Did "hundreds of birds" fall out of the sky in the Netherlands due to a 5G test?

No, while 337 starlings (<5% of the population) and 2 common wood pigeons were found dead in a Netherlands park, this was not due to a 5G test. The birds died 4 months after the only conducted 5G ...
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13 votes
Accepted

Are British plugs safer than all other plugs?

Summary Death rates for cause electric accidents (per million inhabitants and year) do not differ significantly between Ireland (UK type G) and Germany (Schuko), see below (I did not find similar ...
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11 votes
Accepted

Is keyless theft/relay theft a practical threat for vehicles with fob/keyless entry?

Is keyless theft/relay theft a practical threat for vehicles with fob/keyless entry? Are videos demonstrating it happening practical enough? https://www.youtube.com/watch?v=bR8RrmEizVg Police in ...
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  • 1,798
11 votes
Accepted

Can you charge your phone using a non-electrified railway?

What you see in the video is the АЛСН (автоматическая локомотивная сигнализация непрерывного действия) signal, a system for automatic train control used in the ex-Soviet states. Due to the low ...
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11 votes

Do consumer computers include components that can connect to the internet when the computer is apparently turned off?

Let me answer the actual question: Is it true that the Intel Management Engine, and/or similar components in other brands of processor, can connect autonomously to the internet when the ...
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10 votes

Are British plugs safer than all other plugs?

Has anyone any got any statistics on the number of deaths and injuries from electrical plugs in Britain, and compared them to other areas that do not have these safety features in their power plugs? ...
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8 votes

Do fitness trackers make you fatter?

No. Using a tracker does not make you fatter, and that is not what this study claims. Lets start with the participants: Among young adults with a BMI between 25 and less than 40 (so no already ...
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  • 840
8 votes
Accepted

Is there a 12% chance that a solar storm does damage to the electrical grid in the next decade?

This has gone viral. Yes, the risk is high as the article suggests, this number was estimated (or calculated) by physicist Pete Riley, who receives fundings form NASA, NSF, and DoD. His recent ...
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  • 29.8k
5 votes

Could phone and electronics batteries be recharged by a lightning strike?

It is not possible. Nor inside the car or anywhere else. A car is a metal cage (Faraday cage): A Faraday cage operates because an external static electrical field causes the electric charges within ...
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  • 2,856
5 votes
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Do cellphones pose any harm to pacemaker users?

Yes, in some cases. The risk seems to depend on the cell phone and pacemaker involved. Apparently there's no conflict in some cases, while there can be in other cases. The American Heart ...
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  • 4,040
4 votes
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Are criminals wandering around with contactless POS sale terminals helping themselves to small amounts from people's RFID credit/debit cards?

Roger Grimes is a computer security professional. In late 2017, he wrote an article for CSO describing his search for confirmed examples of people having the credit cards skimmed by an RFID reader: I’...
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  • 132k
4 votes
Accepted

Does fully discharging a Lithium-based battery reduce its lifespan?

For a TLDR version, jump to the last paragraph. Since AccuBattery links to another paper than the one they actually cited, I felt like double checking if they represented the paper correctly... and ...
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  • 49.3k
4 votes

Did Marconi steal and patent Jagadeesh Chandra Bose's wireless technology?

Actually The English Wikipedia has a great page about J. C. Bose. Bose went to London on a lecture tour in 1896 and met Italian inventor Guglielmo Marconi, who had been developing a radio wave ...
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  • 2,590
4 votes

Did "hundreds of birds" fall out of the sky in the Netherlands due to a 5G test?

Snopes actually has more details refuting the sequence of events; because tests of 5G use yet unallocated spectrum, they need special regulatory approval. One such test did occur in an area generally ...
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  • 49.3k
4 votes

Is it dangerous to vacuum-clean motherboards (and other electronics)?

Can static electricity build up in vacuum cleaners, and in particular, their nozzles? Yes, vacuum cleaners can indeed build up a noticeable static charge. The amount of charge buildup can vary ...
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4 votes

Can the health of an alkaline battery be determined by bouncing it?

Yes, it can. This video explains why it works This test works equally well for AA, AAA, C, D and 9 Volt alkaline batteries. It is our understanding that the following chemical reactions ...
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3 votes

Does reading off a self-luminous tablet impact the quality of sleep?

Guessing it does not count as science-related: iPads are so bad for your healthy sleep that even Apple offers now a redshifting feature in newer devices. But that is partially because: Evening use of ...
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3 votes

Can hot-plugging an HDMI cable damage the HDMI port?

Hot plugging a connector that is designed to be hot pluggable carries minimal risk, but not zero risk. As mentioned above, Electro Static Discharge (ESD) is always a concern, although one of the jobs ...
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2 votes

Can a "special resistor" save a water heater tank from rust?

The "special resistor" doesn't protect the tank from rust, the sacrificial anode does. The special resistor - or any resistor for that matter - makes the anode last longer, which has been recognized ...
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  • 7,458
2 votes

Do 4K displays use more power, because it is hard for the backlight to shine through those super tiny pixels?

Yes, this is correct, at least some of the time. Here is an image of an LCD display taken with a microscope: The black/white parts at the top of each pixel are the hardware for controlling each of ...
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2 votes

Do 4K displays use more power, because it is hard for the backlight to shine through those super tiny pixels?

Linus is right. On an LCD screen the light travels through the pixel. The controller on each sub-pixel (see groups of three rgb rectangles in dont_shog_me_bro's answer) determines how that light is ...
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  • 668
1 vote

Did "hundreds of birds" fall out of the sky in the Netherlands due to a 5G test?

There is a short report on the swiss national broadcaster, SRF, about the incident, to be found here, in german: https://www.srf.ch/news/wirtschaft/mobilfunk-geruechte-die-wichtigsten-antworten-in-der-...
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1 vote

Have people died by being shocked through the headphone cord of their cell phone?

It seems there's some evidence that you can be shocked through earphones especially during lightning strikes: Listening to MP3s in a storm could blow your mind Some evidence of other shocks non ...
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  • 170
1 vote

Killed by 9V battery (via multimeter)

If the current has a direct pathway to the heart (e.g., via a cardiac catheter or other kind of electrode), a much lower current of less than 1 mA (AC or DC) can cause fibrillation Source: ...
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