# Factual Questions **URL:** https://boards.straightdope.com/c/factual-questions/9.md?page=5 [Latest](https://boards.straightdope.com/latest.md) · [Categories](https://boards.straightdope.com/categories.md) · [Tags](https://boards.straightdope.com/tags.md) **Page:** 6 --- ## [Cars with biometric surveillance of the driver--experiences?](https://boards.straightdope.com/t/cars-with-biometric-surveillance-of-the-driver-experiences/1030634)
**Author:** [@chappachula](https://boards.straightdope.com/u/chappachula)\ **Replies:** 75\ **Last updated:** [July 28, 2026, 6:08pm UTC](https://boards.straightdope.com/t/cars-with-biometric-surveillance-of-the-driver-experiences/1030634 "2026-07-28T18:08:57Z")
All new cars sold in America will soon be required to be spies, performing nonstop biometric surveillance on the driver. 1.Is this only an American requirement, or will it become the international standard? 2.Does any… --- ## [Did French civilians in Normandy not celebrate D-Day for decades?](https://boards.straightdope.com/t/did-french-civilians-in-normandy-not-celebrate-d-day-for-decades/1031927)
**Author:** [@Asuka](https://boards.straightdope.com/u/Asuka)\ **Replies:** 8\ **Last updated:** [July 27, 2026, 9:45pm UTC](https://boards.straightdope.com/t/did-french-civilians-in-normandy-not-celebrate-d-day-for-decades/1031927 "2026-07-27T21:45:43Z")
A claim ive seen here and there online for a few decades now is that “In the aftermath of D-Day most French civilians living in Normandy never celebrated or took part in memorials for American/Allied soldiers because of … --- ## [What kind of reflections are dangerous with a 2W green laser?](https://boards.straightdope.com/t/what-kind-of-reflections-are-dangerous-with-a-2w-green-laser/1031919)
**Author:** [@Cardinal](https://boards.straightdope.com/u/Cardinal)\ **Replies:** 21\ **Last updated:** [July 27, 2026, 1:01pm UTC](https://boards.straightdope.com/t/what-kind-of-reflections-are-dangerous-with-a-2w-green-laser/1031919 "2026-07-27T13:01:26Z")
A student was talking about getting a 2W green laser, because of course burning things with a laser sounds cool. I looked up problems with this idea, and found out about laser protective goggles. I also saw that they eli… --- ## [Electric aircraft -- current range? and what is this aircraft?](https://boards.straightdope.com/t/electric-aircraft-current-range-and-what-is-this-aircraft/1023726)
**Author:** [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Replies:** 17\ **Last updated:** [July 27, 2026, 1:30am UTC](https://boards.straightdope.com/t/electric-aircraft-current-range-and-what-is-this-aircraft/1023726 "2026-07-27T01:30:42Z")
I got to wondering about the current state of Electric Aviation and what is the best range on a single charge. I couldn’t find much bacause most of the google hits were for EVTOL aircraft. Those might get 100 miles, alth… --- ## [Which will heat the house more: braising pot roast in the oven, or on top of the stove?](https://boards.straightdope.com/t/which-will-heat-the-house-more-braising-pot-roast-in-the-oven-or-on-top-of-the-stove/1031748)
**Author:** [@teelabrown](https://boards.straightdope.com/u/teelabrown)\ **Replies:** 30\ **Last updated:** [July 25, 2026, 8:03pm UTC](https://boards.straightdope.com/t/which-will-heat-the-house-more-braising-pot-roast-in-the-oven-or-on-top-of-the-stove/1031748 "2026-07-25T20:03:35Z")
I have a nice chunk of chuck roast I want to braise, then shred for stuffing into taquitos. But the weather is hot, so I want to choose the least house-heating method. Which should I do - turn on the oven to braise it,… --- ## [iPad not charging - what's the logic?](https://boards.straightdope.com/t/ipad-not-charging-whats-the-logic/1031871)
**Author:** [@Llama\_Llogophile](https://boards.straightdope.com/u/Llama_Llogophile)\ **Replies:** 9\ **Last updated:** [July 25, 2026, 2:41am UTC](https://boards.straightdope.com/t/ipad-not-charging-whats-the-logic/1031871 "2026-07-25T02:41:25Z")
My iPad sometimes says “not charging” even when plugged in. I can sometimes guess why this might be - connected to a computer, etc. But in this case, it charges when on but once the cover is closed it won’t charge. Why?… --- ## [Facebook question](https://boards.straightdope.com/t/facebook-question/1031832)
**Author:** [@enipla](https://boards.straightdope.com/u/enipla)\ **Replies:** 22\ **Last updated:** [July 24, 2026, 5:11pm UTC](https://boards.straightdope.com/t/facebook-question/1031832 "2026-07-24T17:11:14Z")
I do have a facebook account. I ONLY use it to check out pictures of our dogs when we have to board them on vacation. So if I go on facebook and search for someone, and find them, will that ping their account? Will they… --- ## [Smoke Detector Question](https://boards.straightdope.com/t/smoke-detector-question/1031860)
**Author:** [@19USMC69](https://boards.straightdope.com/u/19USMC69)\ **Replies:** 27\ **Last updated:** [July 24, 2026, 4:54pm UTC](https://boards.straightdope.com/t/smoke-detector-question/1031860 "2026-07-24T16:54:39Z")
I’m replacing five 22 year old smoke detectors tomorrow. They are interconnected with 120 volt household current and battery backup. The new detectors can be installed individually or interconnected. If I were use the i… --- ## [Depositing checks in an ATM](https://boards.straightdope.com/t/depositing-checks-in-an-atm/1031815)
**Author:** [@mixdenny](https://boards.straightdope.com/u/mixdenny)\ **Replies:** 35\ **Last updated:** [July 23, 2026, 4:56pm UTC](https://boards.straightdope.com/t/depositing-checks-in-an-atm/1031815 "2026-07-23T16:56:56Z")
I typically deposit any checks in the ATM in front of my bank. But you can deposit a check anywhere, I’m pretty sure. So how do those checks get from an ATM across town back to my bank? Does the ATM sequester checks from… --- ## [Are EM waves additive like sound waves? Or do they remain distinct?](https://boards.straightdope.com/t/are-em-waves-additive-like-sound-waves-or-do-they-remain-distinct/1031648)
**Author:** [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Replies:** 22\ **Last updated:** [July 23, 2026, 3:41pm UTC](https://boards.straightdope.com/t/are-em-waves-additive-like-sound-waves-or-do-they-remain-distinct/1031648 "2026-07-23T15:41:27Z")
Background: When two sonic sine waves of close frequency occur at the same time, we hear them as the average of the two frequencies, with the amplitude pulsing at the rate of the difference between the two frequencies (… --- ## [The Union was able to draft slaves in the Civil War?](https://boards.straightdope.com/t/the-union-was-able-to-draft-slaves-in-the-civil-war/1031753)
**Author:** [@Edward\_The\_Head](https://boards.straightdope.com/u/Edward_The_Head)\ **Replies:** 7\ **Last updated:** [July 23, 2026, 12:37pm UTC](https://boards.straightdope.com/t/the-union-was-able-to-draft-slaves-in-the-civil-war/1031753 "2026-07-23T12:37:31Z")
I’ve been doing some genealogical research in some local papers. I found a draft list from The Valley Register of Middletown Maryland from May 20, 1864. I was just skimming the list to see what names I may know, when at … --- ## [The California Economy](https://boards.straightdope.com/t/the-california-economy/1031790)
**Author:** [@threeorangept2](https://boards.straightdope.com/u/threeorangept2)\ **Replies:** 13\ **Last updated:** [July 21, 2026, 5:30pm UTC](https://boards.straightdope.com/t/the-california-economy/1031790 "2026-07-21T17:30:50Z")
I have in recent months heard the claim that California has the fourth (sometimes third) largest economy in the world. Presumably one and two would be the rest of the USA and China. This would mean, however, that Califor… --- ## [Speed of light / reflection question](https://boards.straightdope.com/t/speed-of-light-reflection-question/1031814)
**Author:** [@Lucas\_Jackson](https://boards.straightdope.com/u/Lucas_Jackson)\ **Replies:** 12\ **Last updated:** [July 21, 2026, 3:39pm UTC](https://boards.straightdope.com/t/speed-of-light-reflection-question/1031814 "2026-07-21T15:39:26Z")
In this video, a camera that can take a trillion frames per second captures a photon entering the frame (headed for an apple). The technician explains that you can see the photon(s) coming by the reflection on the table… --- ## [Broadcast sports virtual ads aren't "targeted" yet, are they?](https://boards.straightdope.com/t/broadcast-sports-virtual-ads-arent-targeted-yet-are-they/1031810)
**Author:** [@Hampshire](https://boards.straightdope.com/u/Hampshire)\ **Replies:** 5\ **Last updated:** [July 21, 2026, 12:54pm UTC](https://boards.straightdope.com/t/broadcast-sports-virtual-ads-arent-targeted-yet-are-they/1031810 "2026-07-21T12:54:28Z")
Because I source industrial manufacturing parts on-line all day at work my ad feed while browsing are never ending ads for stuff I purchase. Even at home they’ve found a way to link to my work browsing history and fill a… --- ## [B&H Photo and Shabbat](https://boards.straightdope.com/t/b-h-photo-and-shabbat/1030999)
**Author:** [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Replies:** 31\ **Last updated:** [July 20, 2026, 8:32pm UTC](https://boards.straightdope.com/t/b-h-photo-and-shabbat/1030999 "2026-07-20T20:32:51Z")
For those not familiar, B&H is the preeminent photographic equipment source. They have a huge store in New York City but do most of their business through their web site. I don’t know if they are Jewish owned but they h… --- ## [Water flowing over a weir: X inches deep means how many gallons/second per foot?](https://boards.straightdope.com/t/water-flowing-over-a-weir-x-inches-deep-means-how-many-gallons-second-per-foot/1031772)
**Author:** [@Timz](https://boards.straightdope.com/u/Timz)\ **Replies:** 9\ **Last updated:** [July 20, 2026, 4:54pm UTC](https://boards.straightdope.com/t/water-flowing-over-a-weir-x-inches-deep-means-how-many-gallons-second-per-foot/1031772 "2026-07-20T16:54:57Z")
There must be a pretty simple first-approximation formula, assuming standard gravity and water density, an infinite reservoir behind, no ripples, no turbulence, just constant smooth flow. If the water level in the reserv… --- ## [Smartphones vs. headphones](https://boards.straightdope.com/t/smartphones-vs-headphones/1031644)
**Author:** [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Replies:** 13\ **Last updated:** [July 19, 2026, 11:42am UTC](https://boards.straightdope.com/t/smartphones-vs-headphones/1031644 "2026-07-19T11:42:36Z")
Why can you use a smartphone while it’s plugged in but not a headphone? --- ## [Can a power surge cause a clock to go ahead?](https://boards.straightdope.com/t/can-a-power-surge-cause-a-clock-to-go-ahead/1031357)
**Author:** [@CC](https://boards.straightdope.com/u/CC)\ **Replies:** 25\ **Last updated:** [July 18, 2026, 2:42pm UTC](https://boards.straightdope.com/t/can-a-power-surge-cause-a-clock-to-go-ahead/1031357 "2026-07-18T14:42:58Z")
We have two electric clocks that do NOT have battery backup. Just digital clocks - both on radios. We occasionally have a brief power outage and afterwards, one clock will be just a couple minutes behind and one on the… --- ## ['Get smart!' \[Jewish phrase\]](https://boards.straightdope.com/t/get-smart-jewish-phrase/1030961)
**Author:** [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Replies:** 42\ **Last updated:** [July 18, 2026, 1:25pm UTC](https://boards.straightdope.com/t/get-smart-jewish-phrase/1030961 "2026-07-18T13:25:44Z")
I understand that if someone tells someone to ‘get smart’ (Jewish phrase), he’s saying, ‘You’re being an idiot. Look at the situation like you’re n intelligent person.’ (More or less.) I’m not Jewish, but I get the jo… --- ## [Authority of the Hawaii Supreme Court and the USSC](https://boards.straightdope.com/t/authority-of-the-hawaii-supreme-court-and-the-ussc/1031758)
**Author:** [@Melbourne](https://boards.straightdope.com/u/Melbourne)\ **Replies:** 4\ **Last updated:** [July 18, 2026, 12:36pm UTC](https://boards.straightdope.com/t/authority-of-the-hawaii-supreme-court-and-the-ussc/1031758 "2026-07-18T12:36:14Z")
I’ve just read a cheap polarizing engagement-driven online article about a cheap political attack by Justice Todd Evens of the Hawaii Supreme Court, on the cheap politics of John Roberts and the US Supreme Court, in whic… --- ## [Can polar-orbit satellites launch out of Florida?](https://boards.straightdope.com/t/can-polar-orbit-satellites-launch-out-of-florida/1031733)
**Author:** [@Timz](https://boards.straightdope.com/u/Timz)\ **Replies:** 3\ **Last updated:** [July 17, 2026, 8:52pm UTC](https://boards.straightdope.com/t/can-polar-orbit-satellites-launch-out-of-florida/1031733 "2026-07-17T20:52:33Z")
Many? Most? satellites going up these days are in close-to-polar orbits, so you’d like the rocket to launch near northward or near southward. So heading south out of Vandenburg is fine, but not out of Florida. Is it for … --- ## [My shaving soap doesn't work anymore](https://boards.straightdope.com/t/my-shaving-soap-doesnt-work-anymore/1031436)
**Author:** [@jsc1953](https://boards.straightdope.com/u/jsc1953)\ **Replies:** 25\ **Last updated:** [July 17, 2026, 5:34am UTC](https://boards.straightdope.com/t/my-shaving-soap-doesnt-work-anymore/1031436 "2026-07-17T05:34:11Z")
All my adult life, I’ve used a brush and soap to shave. (Why, you may ask? Dunno. I like old-fashioned things, I guess.) I’ve never been loyal to any particular brand. But recently I bought a new bar, and it failed … --- ## [Where's the blue? (reflecting pool)](https://boards.straightdope.com/t/wheres-the-blue-reflecting-pool/1031664)
**Author:** [@california\_jobcase](https://boards.straightdope.com/u/california_jobcase)\ **Replies:** 10\ **Last updated:** [July 17, 2026, 12:52am UTC](https://boards.straightdope.com/t/wheres-the-blue-reflecting-pool/1031664 "2026-07-17T00:52:34Z")
OK, they’re draining the reflecting pool again. All the pictures I’ve seen show no hint of the blue color that’s supposed to be there. Is it just because the color is obscured by scum from the drained water? --- ## [Spirulina Farts?](https://boards.straightdope.com/t/spirulina-farts/340885)
**Author:** [@cowgirl](https://boards.straightdope.com/u/cowgirl)\ **Replies:** 19\ **Last updated:** [July 16, 2026, 10:48pm UTC](https://boards.straightdope.com/t/spirulina-farts/340885 "2026-07-16T22:48:03Z")
My husband has recently been consuming a lot of Greens+, spirulina, that sort of stuff. Perhaps coincidentally, he has been letting go the most toxic, potent, vile farts I have ever had the displeasure of experiencing. … --- ## [Why does Louisiana refer to districts as parishes?](https://boards.straightdope.com/t/why-does-louisiana-refer-to-districts-as-parishes/319804)
**Author:** [@levdrakon](https://boards.straightdope.com/u/levdrakon)\ **Replies:** 51\ **Last updated:** [July 16, 2026, 7:16pm UTC](https://boards.straightdope.com/t/why-does-louisiana-refer-to-districts-as-parishes/319804 "2026-07-16T19:16:02Z")
To me a parish is the area serviced by the local church. But I’ve never heard anyone refer to geographical area as a parish. Is Louisiana the only place that does that? Why? --- ## [What motor oil should I choose? 0w-40 or 5w-40?](https://boards.straightdope.com/t/what-motor-oil-should-i-choose-0w-40-or-5w-40/1031645)
**Author:** [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Replies:** 13\ **Last updated:** [July 15, 2026, 3:23pm UTC](https://boards.straightdope.com/t/what-motor-oil-should-i-choose-0w-40-or-5w-40/1031645 "2026-07-15T15:23:26Z")
I checked and my car (Audi Q5) can use either. My last service they put in 5w-40 oil but I can only find 0w-40 oil at my market (oil that also meets Audi’s strict standards…I don’t understand it all but it has the right… --- ## [Enforceability of those multiple reserved parking spots at retailers](https://boards.straightdope.com/t/enforceability-of-those-multiple-reserved-parking-spots-at-retailers/1031631)
**Author:** [@Hampshire](https://boards.straightdope.com/u/Hampshire)\ **Replies:** 64\ **Last updated:** [July 14, 2026, 11:11pm UTC](https://boards.straightdope.com/t/enforceability-of-those-multiple-reserved-parking-spots-at-retailers/1031631 "2026-07-14T23:11:09Z")
So of course if you park in a handicapped spot or in front of a hydrant you can expect a hefty ticket and possible towing. But how enforceable are those “other” spots retailers have? Employee of the month, hero/vet parki… --- ## ["False" noises like the camera noise that cell phones make](https://boards.straightdope.com/t/false-noises-like-the-camera-noise-that-cell-phones-make/837183)
**Author:** [@iiandyiiii](https://boards.straightdope.com/u/iiandyiiii)\ **Replies:** 87\ **Last updated:** [July 14, 2026, 9:46am UTC](https://boards.straightdope.com/t/false-noises-like-the-camera-noise-that-cell-phones-make/837183 "2026-07-14T09:46:13Z")
Are there any other noises made by technology that mimic a past noise that was an intrinsic part of the action, like the subject noise? --- ## [Did the Soviet Navy ever get close to closing the submarine technology gap with the U.S. Navy before the Cold Wars end?](https://boards.straightdope.com/t/did-the-soviet-navy-ever-get-close-to-closing-the-submarine-technology-gap-with-the-u-s-navy-before-the-cold-wars-end/1031642)
**Author:** [@spacecadet86](https://boards.straightdope.com/u/spacecadet86)\ **Replies:** 11\ **Last updated:** [July 13, 2026, 8:05pm UTC](https://boards.straightdope.com/t/did-the-soviet-navy-ever-get-close-to-closing-the-submarine-technology-gap-with-the-u-s-navy-before-the-cold-wars-end/1031642 "2026-07-13T20:05:23Z")
What was the status of Soviet submarine development around 1989-1990? How great or small was their technological inferiority? Did Soviet submarines ever outperform U.S. submarines in any way? --- ## [How does a mariner arrange to have a rarely used drawbridge opened?](https://boards.straightdope.com/t/how-does-a-mariner-arrange-to-have-a-rarely-used-drawbridge-opened/1031465)
**Author:** [@WildaBeast](https://boards.straightdope.com/u/WildaBeast)\ **Replies:** 49\ **Last updated:** [July 13, 2026, 4:50pm UTC](https://boards.straightdope.com/t/how-does-a-mariner-arrange-to-have-a-rarely-used-drawbridge-opened/1031465 "2026-07-13T16:50:16Z")
So I went down a rabbit hole of reading about the historic draw bridges around California’s Delta Region, which led me to this video of the Miner Slough Bridge opening. While the bridges on the main channel of the river… [Previous page](https://boards.straightdope.com/c/factual-questions/9.md?page=4) [Next page](https://boards.straightdope.com/c/factual-questions/9.md?page=6)