Red Iron Crown Posted July 9, 2015 Share Posted July 9, 2015 (edited) "It's true, a car protects you from lightning. Because of the rubber tires." Basically what one of my teachers said one day. Funny thing is, I watched a CGP Grey video the previous night saying how cars are faraday cages, and that's how they protect you.I had a facepalm in my head when the teacher said that, and very nearly had one IRL.Your teacher is right and CGP Grey is wrong in this case. Lightning is looking for a low resistance path to the ground, the rubber tires are good insulators and prevent that. Faraday cages (of which a car is a very poor one) don't protect against lightning.Turns out this was wrong, please facepalm at it. Edited July 10, 2015 by Red Iron Crown Link to comment Share on other sites More sharing options...
Sampa Posted July 9, 2015 Share Posted July 9, 2015 RULES:*NEVER make fun of anyone specifically. Just mention the thing they said.*STAY ON TOPIC*Do NOT refer to other's posts on this forum. That hasn't ended well in the past.So what are some things you've heard from some people or things that made you facepalm? It can be related to anything, space, reading, history, etc.Mine, well, Michael Bay's impression of stopping an asteroid with a Shuttle. GG Bay GG. Armageddon.seems off topic but isn't...Just read the two-three rules as NEVER stay on topic! *facepalm* Link to comment Share on other sites More sharing options...
Hcube Posted July 9, 2015 Share Posted July 9, 2015 Physics (thermodynamics) test (highschool) : "the total energy of a capsule re-entering the atmosphere is Q=x J and does not change throughout re-entry. The capsule radiates away -y J during re-entry." And the question was about work, and energy received by the capsule. (i know it's a rather stupid exercise but you know)Then the last "easy" question : what is causing the capsule to heat up ? Me : "air compression in front of the capsule."2 weeks later---> Teacher gives back copies : i got 0 at that last question. Physics teacher : "no it's friction"Me : intense facepalm. I couldn't convince him. Link to comment Share on other sites More sharing options...
ChrisSpace Posted July 10, 2015 Share Posted July 10, 2015 Here's what I heard at the end of some youtube video:So, what have we learned today? Don't jump off buildings, you will die.... BUT THAT'S JUST A THEORY! THANKS FOR WATCHING! Link to comment Share on other sites More sharing options...
lajoswinkler Posted July 10, 2015 Share Posted July 10, 2015 (edited) NASA's Facebook page offers great quantities of stupid comments. Here's one made 12 hours ago on the latest Pluto-Charon photo:The space behind it looks so dark, I guess it's because there's so little sun out there to light it up.Also, people who ask questions about New Horizons such as this one:Is there astronomers in it? Or just a controlled craft?Honestly, how do they not kill themselves by forgetting how to breathe? Edited July 10, 2015 by lajoswinkler Link to comment Share on other sites More sharing options...
moronwrocket Posted July 10, 2015 Share Posted July 10, 2015 Your teacher is right and CGP Grey is wrong in this case. Lightning is looking for a low resistance path to the ground, the rubber tires are good insulators and prevent that. Faraday cages (of which a car is a very poor one) don't protect against lightning.[citation needed]Lightning doesn't necessarily choose the absolute lowest resistance path to ground. The electrons actually flow in stages of a few hundred feet at a time. The tire itself might not conduct electricity, but the centimeters between the auto body and ground is nothing compared to the thousands of feet the electrons have already traveled. Faraday cages absolutely protect against lightning - they are commonly used in "lightning simulators"https://en.wikipedia.org/wiki/Faraday_cageOlder all-metal skin cars are better at protecting than newer cars with their plastic shells. That being said, you still should not do anything stupid - don't open a window, don't touch the exterior, etc.http://www.accuweather.com/en/weather-news/cars-can-be-safe-place-during/17283636Lightning bolts are tens to hundreds of thousands of amps, and the current in two paths will depend on the ratio of 1/(resistance) between them. So a metal-ish car with a few ohms and a person with a skin resistance of a hundred thousand ohms (touching the car metal in two places) can cause several amps to flow through your body - more than enough to kill you. A few inches of airgap makes your resistance now hundreds of millions of ohms or more, enough to be mostly safe.http://hyperphysics.phy-astr.gsu.edu/hbase/electric/lightning2.htmlEverything lightning strike is actually several "strikes" - so the old adage "lightning never strikes twice in the same place" is wrong. Even a consumer video camera should be able to capture the lightning stages.https://www.youtube.com/watch?v=RLWIBrweSU8&feature=youtu.be&t=165 Link to comment Share on other sites More sharing options...
Red Iron Crown Posted July 10, 2015 Share Posted July 10, 2015 Perhaps I need to facepalm. Thanks for the references and correction. Link to comment Share on other sites More sharing options...
vinster7 Posted July 10, 2015 Share Posted July 10, 2015 The moon has no gravity - 6th grade science teacher Link to comment Share on other sites More sharing options...
Tex_NL Posted July 10, 2015 Share Posted July 10, 2015 (edited) At work we have an intern, and he is a bit dimwitted. This morning while we were sorting out crates that just came in on the daily delivery truck he asked me: "Where do I put the crates for 'customer X'?" "Put them over here next to 'customer Y'?" I replied. "Oh. Normally I put them over there."AAARRRGGGHHHH! If you normally put them over there then don't ask me where to put them you moron! Edited July 10, 2015 by Tex_NL Link to comment Share on other sites More sharing options...
FireFaced Posted July 10, 2015 Share Posted July 10, 2015 The moon has no gravity - 6th grade science teacherWhen I was really young, I think I believed that. An adult saying that, is just really facepalm-inducing. Link to comment Share on other sites More sharing options...
vinster7 Posted July 10, 2015 Share Posted July 10, 2015 Infact I corrected my 6th grade science teacher alot... Link to comment Share on other sites More sharing options...
FireFaced Posted July 10, 2015 Share Posted July 10, 2015 Infact I corrected my 6th grade science teacher a lot...lol. Guys, to be a teacher, you need to know stuff! Link to comment Share on other sites More sharing options...
FishInferno Posted July 10, 2015 Share Posted July 10, 2015 So my mum and I were standing outside last evening waiting for the ISS to pass over. My little cousin asks what we're doing, and I explain it to him. But then he asks:So how loud will it be?Me: Umm... it's a thing in space.Yeah, but how loud is it going to be?in all fairness, it was a little kid, and kids generally associate airplanes, which move quickly though the sky, with loud noises. So it would be perfectly natural for his little-kid-logic to think that something moving fast through the sky to be loud. Link to comment Share on other sites More sharing options...
windows_x_seven Posted July 10, 2015 Share Posted July 10, 2015 "Alien Illuminati Agenda" Kerbals are Illuminati. Link to comment Share on other sites More sharing options...
CornHuskerKenny Posted July 11, 2015 Share Posted July 11, 2015 This comes from my middle school science teacher:"On Apollo 13, the astronauts were using the engine to get to the moon, but the engine blew up. The only reason they got home, was because they were lucky."The class then watched the movie "Apollo 13", which proved her wrong. However, she still insists that she's right, and the movie is wrong.*facepalm*Disclaimer: The story is passed to me from a friend, and may be inaccurate to an extent. Link to comment Share on other sites More sharing options...
Tex_NL Posted July 11, 2015 Share Posted July 11, 2015 (edited) This comes from my middle school science teacher:"On Apollo 13, the astronauts were using the engine to get to the moon, but the engine blew up. The only reason they got home, was because they were lucky."The class then watched the movie "Apollo 13", which proved her wrong. However, she still insists that she's right, and the movie is wrong.*facepalm*Disclaimer: The story is passed to me from a friend, and may be inaccurate to an extent.Of course you're correct it wasn't the engine that blew but instead one of the cryo tanks. But you can't deny a large dose of luck was involved. Edited July 11, 2015 by Tex_NL Link to comment Share on other sites More sharing options...
ChrisSpace Posted July 11, 2015 Share Posted July 11, 2015 A large portion of people in America/Australia seem to think NASA is the only capable space program in existence. Link to comment Share on other sites More sharing options...
Sampa Posted July 12, 2015 Share Posted July 12, 2015 Physics (thermodynamics) test (highschool) : "the total energy of a capsule re-entering the atmosphere is Q=x J and does not change throughout re-entry. The capsule radiates away -y J during re-entry." And the question was about work, and energy received by the capsule. (i know it's a rather stupid exercise but you know)Then the last "easy" question : what is causing the capsule to heat up ? Me : "air compression in front of the capsule."2 weeks later---> Teacher gives back copies : i got 0 at that last question. Physics teacher : "no it's friction"Me : intense facepalm. I couldn't convince him.Air compression CAUSES friction! Link to comment Share on other sites More sharing options...
Thomas988 Posted July 12, 2015 Share Posted July 12, 2015 This one is actually something I used to think when I was younger.Whenever I'd be reading an astronomy book and see a picture of Jupiter, more times than not would be a caption that read "Jupiter is so large it could fit over 1,000 Earth in it!" However, I would always say to myself "no way could I fit 1,000 Earths in just that amount of space!" What I failed to comprehend is that Jupiter is not a two-dimensional sphere, and does indeed have depth. Link to comment Share on other sites More sharing options...
windows_x_seven Posted July 12, 2015 Share Posted July 12, 2015 (edited) Fully ambidextrous here, along with a mild case of the whole directional dyslexia thing that usually accompanies it. I was forced to write with my right hand in school (since left-handed people are children of Satan or some BS like that), so my left-hand writing is a bit less precise (yet still legible).IQs were lost today.Why are people allowed to teach such thing in schools? Edited July 12, 2015 by windows_x_seven Link to comment Share on other sites More sharing options...
Dark Junior Posted July 12, 2015 Share Posted July 12, 2015 The politician who think's we'll run out of sun if we use solar power.(I"M NOT JOKING! I HEARD ABOUT THIS!) Link to comment Share on other sites More sharing options...
razark Posted July 12, 2015 Share Posted July 12, 2015 The politicians who think's we'll run out of sun if we use solar power.You made a slight typo. Link to comment Share on other sites More sharing options...
ChrisSpace Posted July 12, 2015 Share Posted July 12, 2015 The politician who think's we'll run out of sun if we use solar power.As Tony Abbot once said:Our nation's future is definitely in coal, sunlight and wind won't last forever. Link to comment Share on other sites More sharing options...
windows_x_seven Posted July 12, 2015 Share Posted July 12, 2015 (edited) This channel.+rep to whoever manages to watch all of its videos and come out intact.Have a sample:NOTICE: THE AUTHOR OF THIS VIDEO SWEARS A LOT IN THIS VIDEO zelda is a ripoff from minecraft Edited July 12, 2015 by windows_x_seven Link to comment Share on other sites More sharing options...
Hcube Posted July 12, 2015 Share Posted July 12, 2015 Air compression CAUSES friction!Yeah obviously, but the main heating factor is the superheated air in contact with the capsule, and anyway when i wrtoe air compression, the teacher saying "no it's not" is wrong... Link to comment Share on other sites More sharing options...
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