â¢ Related QuestionsIf we have an LED that comes on and off for an equal amount of time but the time period so short that our eyes cannot catch the frequency of LED, the LED looks always on. Why doesn't it looks always off, since the time period is the same?
Because your eye is not a digital sampling device. A digital sampling device whose period is the same as the event being sampled would show all on or all off based upon the phasing of the sampling being at the time when it is on or at the time when it is off.Your and all human eyes are based upon persistence of vision wherein the image is blurred together. watching a changing pattern will give you a blur of all the motion... if the LEDs are on and off equal times it would look 50% as bright as it would if they were on 100% of the time.Now don't get confused with stop images caused by viewing moving images under flourescent light which is on and off (strobing) at the line frequency - there you only see the images that are illuminated and when blurred together with the persistence of vision it may appear to stop or move slowly depending upon the difference in strobe frequency and moving speed.
If we have a LED that becomes on and off for the equal amount of time but the time period is very less that our eyes cannot catch the frequency of LED, we see that the LED looks always on. Why doesn't it looks always off, as time period is same?
What was Richard Feynman like as a PhD adviser?
Apparently, terrible. It's not so uncommon amongst great scientists; the best athletes don't always make the best coaches. Feynman never compromised on following his interests, and his interests, as varied as they were from molecular biology to painting, were not in advising PhD students.(Perhaps because in general graduate students are a pain in the ass, living poor, hungry and with uncertain job prospects; but mostly likely they couldn't keep up with the Feynman method - pause think write down the answer.
)And I say that having gone to Princeton to study physics over MIT to study engineering after reading about his experience and research at the former as a PhD student; and generally being inspired by Feynman's teaching, humor and integrity in most areas of life.The guy you really want to ask this question about is John Wheeler, who by all accounts, including Feynman's in his Nobel speech and writings elsewhere, and by the empirical evidence of his success with students, was truly incredible. (Kip Thorne also discusses Wheeler's talent in the area in Black Holes and Time Warps.
org/nobel_prizes/physics/laureates/1965/feynman-lecture.htmlThe irony of course is that I've never heard the principles of being a great PhD advisor expressed so clearly as by Feynman in that speech. And the fact he even chose to talk about it is remarkable.
What's the dumbest question you've seen on school homework?
So this was on an exam.I didnt personally go through this but it was a popular story in my university.So the course was a Philosophy course, there was quite a bit of memorization required if you want to do well in this course. So when the final exam approached, everyone is memorizing their brain off.
Then the final exam had an essay part, which covers about 60% of the exam. The essay question isWhy?(flip table violentlyThat will probably be my initial response if I were the person writing the exam. I spent all those all-nighters remembering every single word on the book and what is this shit??Apparently, half of the class couldnt figure out what the heck the professor expects from them and failed terribly. But there was this one guy who surprisingly left earlier than anyone did during the exam.and yep, he got 100% on the essay part.Guess what he wrote?Why not.To speak for the other 150 people on that exam, this might be the dumbest question theyve had in their lives at that point.But yes, I think the university would surely re-evaluate the results :))Disclaimer: not sure if this story is true or greatly exaggerated, but it does sound like what the professors in my university would do.
Which tweet disturbed you today?
Now Why this?No doubt it is funny. Main pagal ho gya has has ke.But disturbing to see how polar opposite the world has become. You just say a word in praise of something, the other side starts trolling you.First in support of PM Modi call to light up diyas, candlesThen Omar abdullah said something offending entire India and some others mocked our PM.
This caused something else to trendArticle 370 and Burnol.WHAT ISSUE DO I HAVE ?People turning reactionary and easily offended on the lines like AB HUM DIKHATE HAINToday, you have to chose between this or that.If I chose something good from this and something good from that then I will be called 2 faced. You have to chose one side. This will call debates not discussion. The roughness with which we debate will lead to clashes in future. Won't they. Today we have debates with panel members with the intention to pin him/her down and not to learn something from them. Today a large group on quora, twitter, fb is not seeking truth but doing just the opposite. And this is on both sides of the narrative today. Conservatives cannot find anything good with the liberals and liberals think conservatives are primitives.Being objective is seen either as confused, 2 faced, dogla etc etc.
With Brazil and China blocking NSG membership of India, how would BRICS be affected?
NSG issue is being blown out of proportion and India will continue to do as good as it is doing now from Nuclear Fuel perspective. India already enjoys exception in this regard from major Nuclear suppliers.For India, it is more an issue of label rather than anything else. You know our Prime Minister, it was more about showmanship and he infact did try to peacefully garner support for our NSG bid and was mostly successful.Remember, support of 99% members is substantial, considering NSG itself was founded in reaction to Indias First Nuclear Test.Other than that, some hard truths for India and the world came in the form of persistent resistance from China.
Chinese Mentality has been bared before the world, it is a country which can not be reasoned with. There is a total disregard for mutual understanding and betterment of relations between India and China.Standing alone against India once again brings at the forefront Chinese bullying tactic. Good that India is progressing well with regards to its relations with US, Japan and other South-East Asian countries. All of which at some point will be subjected to Chinese aggressionLastly, this was be expected from a country which in fact is the prime proliferator of Nuclear arms by giving it to rogue countries such as North Korea and pakistan
Did some black slaves love their white slave owners?
Yes, in the same way a dog loves his owner. We didn't know any other life especially if you were born into slavery. Some of my ancestors actually begged to stay when asked to leave the plantation. They only left when the master gave them 600 acres of land in the neighboring town. But understand the power dynamic and the reasons. Some slaves stayed with one master their whole lives and grew up side by side with white families. Had children together and even sometimes were buried side by side. Also if you were obedient then sometimes you'd live a fairly decent life without beatings or extreme hardships. My grandfather told me that his family told him that at one point they didn't know they were slaves. They lived in separate housing and had a black overseer and would rarely see white people in their little community. As long as they worked for free and met their quota then they could live a good life. So when they came and told them they had to leave alot of them cried and begged to stay. Some left immediately but circled back after facing dehydration and hunger. So the answer to your question is yes but obviously because of their situation. Instead of living a miserable life alot of slaves made the best of their situation and settled instead of constantly revolting.
What is the most ridiculous thing you have heard from a creationist?
First, may I thank Bradley Betts for the banana story. I laughed a lot, then checked up since I could not believe it was not deliberate irony. But its not!Anyway, my favourite is the eye story. It goes like this - consider the eye, a perfect piece of design that came to humans in perfect working form.Now as most people know the eye does not do seeing - it does receiving. Wavelengths of light. The seeing bit is in the even more clever brain. But it gets sillier of course.
Our eye is not the only eye. First we share the eye with a vast range of animals of all forms. And not all those eyes are exactly the same - they vary depending on what the animal using them needs. Cats see better than we do at night.Even more silly is that there are scores of different types of eye, from the very porimitcve to our more complex eye. This link helps Eye - WikipediaThen comes the riposte. But how could it evolve? Well actually the most primitive creatures of all respond to light. And they have no eyes. But any form of energy will produce a response - and that is all the eye, however simple or complex, does. And we of course understand that given enough time and enough opportunities almost anything is possible