Talk:1531: The BDLPSWDKS Effect

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Isn't part of the Doppler joke the fact that it is a fire truck, as emergency vehicle sirens are very often used as an example of the Doppler effect? 13:18, 30 May 2015 (UTC)

Doesn't the reference to the "Doppler" effect refer to the fact that the Doppler effect may distort the meaning of words in a tonal language, thus making it harder to perceive the word being shouted out of the firetruck? A-jay (talk) 07:52, 29 May 2015 (UTC)

I thought this too - tonal languages will inevitably suffer more from Doppler distortion than non-tonal ones, so it's going to take the listener longer to react to it. Obviously, that's not the sole cause for the delay with the BDLPSWDKS effect, but it's surely a contributing factor. Bish (talk) 11:22, 29 May 2015 (UTC)

I think it is a bit more complex than effect mentioned having an individual referent. It becomes complex because the language level, for example, interacts with the physics level. (I think this is the joke, that such random effects from different fields can actually interrelate in some bizarre scenario) A tonal language would be much more susceptible loss of meaning due to blue shift from the doppler effect than a nontonal language. Shouting red is also probably a reference to the 'red-shift' in the doppler effect, which, depending on the speed of the truck may distort the sound the shout or make it unintelligible. At sufficient speed, this would also distort the actual color of the firetruck, which is a topic Randall discussed in one of the What-If's about traffic lights and should probably be linked here. --MareCrisium (talk) 08:15, 29 May 2015 (UTC)

I thought of the red being a redshift as well, but what the heck is "GREEN" then (rather than "BLUE")? Odysseus654 (talk) 09:05, 29 May 2015 (UTC)

I wonder if the reference to whether the language has a word for "firetruck" is a Sapir Whorf reference? If there's no word for firetruck, the listener (victim?) is likely to be more confused by the situation than a listener who can at least recognize what kind of vehicle is about to kill him/her (Curses! There's no sexless personal pronoun in this language!) So the reaction time of the first person is likely to be longer than that of the second person.

"They/them/etc." has been the accepted sexless personal pronoun for a long time (in the order of centuries), even in the singular. The only people who say you shouldn't use it for such a purpose are the same ones who say you shouldn't split an infinitive despite it having been acceptable for centuries, simply because it's impossible to split infinitives in Latin. -- 19:42, 29 May 2015 (UTC)

There's a whole class of psychology experiments (with both human and animal subjects) that uses reaction-time as a measure of degree of understanding in various situations. Is this effect named after a famous experimental psychologist? If so, Randall may have to issue an update to this cartoon... -- Ribbit (talk) (please sign your comments with ~~~~)

If you think English has no sexless personal pronoun you *clearly* haven't read comic 145. Ahem... --MareCrisium (talk) 08:49, 29 May 2015 (UTC)

Off topic, but I agree 'them' is a sufficient pronoun in this case, since you've already specified the singular 'listener'. Bish (talk) 11:22, 29 May 2015 (UTC)

To the best of my knowledge, the Bernoulli effect is, in fact, responsible to the aerodynamic lift. While it is correct that most people trying to explain aerodynamic lift use an incorrect explanation, the incorrect part has nothing to do with Bernoulli, as implied by the explanation. Shachar (talk) 09:53, 29 May 2015 (UTC)

The Bernoulli effect describes how pressure distribution changes with speed, and needs to be understood if you want to fully grasp all the science behind it. That being said, there isn't an intuitive way to grasp how airspeed varies across a wing's surface which ultimately means that any accurate explanation dependent on the Bernoulli effect goes well beyond the scope of a layperson's understanding. It's better to note that wings are tilted to push the airflow downward and for every action their's an equal and opposite reaction.(User talk:Some Guytalk) -- 11:36, 29 May 2015 (UTC)

Um, I'll give you half points – it depends on what type of wing you're talking about. You can have a "high lift" type wing fly straight and level and still provide plenty of lift. But a low chord wing (eg "fighter jet style") more greatly depends on forward speed and angle of attack to stay up than the lift provided by the wings. Needless to say, airplanes make people think - and too often the more people think about them, the more confused they get. Jarod997 (talk) 13:10, 29 May 2015 (UTC)

There's a difference between saying this is how wings generate lift and this is the only factor in the equation. On top of which angle of attack is not defined by the zero lift angle. that being said, every scrap of airfoil data I've ever seen shows a proportional relationship between (angle of attack - zero lift angle of attack) and CL (and by extension lift). Is that everything a professional needs to know about aerodynamics? Far from it. Is it an adequate explanation for laypeople? As far as I'm concerned, yes.--Someguy173.245.54.156 20:57, 29 May 2015 (UTC)

"The Peltzman effect refers to how regulations intended to increase safety are ineffective or counterproductive. This is likely referenced by the observer responding to a dangerous situation more slowly if the language he is warned in has a word describing the object he's in danger from ("firefighter") than if the language didn't." The comic states that the person reacts more *quickly* if the language has a word for firefighter... (talk) (please sign your comments with ~~~~)

I think it's actually about how the firefighter has gotten himself into a dangerous situation due to the feeling of safety he has from being in a modern firetruck, since a major case of the Peltzman effect is that increased car safety leads us to drive at higher speeds. The innocent pedestrian is less safe because the firefighter is driving more recklessly. Not-my-username (talk) 16:10, 29 May 2015 (UTC)