Stupid Definition and 314 Threads

  1. gibsnax

    How Many Eggs to Turn a 40lb Flywheel in a Vacuum?

    TL;DR Summary: How many large AA chicken eggs does it take to turn a 40lb flywheel 1 revolution in a vacuum. Me and my friends are stupid and somehow we got to thinking how much energy is in an egg. We decided to measure this in egg power, or how many eggs it takes to turn a 40 lbs fly wheel 1...
  2. DEvens

    Optimizing Round-Off Accuracy in Source Spectrum Calculations

    So the sequences was the following. Data was provided for a parameter in a standardized situation. This was a source spectrum for a total volume of material. We needed the source spectrum per cubic meter. There are 100,016 cubic meters in the total volume. Simple division. So then I come...
  3. Eclair_de_XII

    I Learn the Truth about Integrals of 1/x: Debunking Common Misconceptions

    Let's take an integral##−\int_1^e\frac{dx}{x}##. On one hand, this is equal to ##-\ln(x)|_1^e##. But on the other, ##−\int_1^e\frac{dx}{x}=\int_1^e\frac{dx}{-x}##. If I assume that the integral of this is ##\ln⁡(-x)|_1^e##, then I'd be really stupid since ##\ln## is not even defined over the...
  4. I

    Simple Finite Square Well Problem help *Ignore, made stupid mistake*

    I've tried to carry out the solution to this as a normal 2nd order Differential Equation ##\psi ##'' - ##-k^2 \psi ## = 0 Assume solution has form ##e^{\gamma x}## sub this in form ##\psi## and get ##\gamma ^2## ##e^{\gamma x} ## + ##k^2 e^{\gamma x}## = 0 Solution is ##\gamma## = 0 or ##k^2##...
  5. atommo

    Stupid question relating to electric induction

    Hi, I've been interested in the science behind electrons/magnetism for quite a while. I've been learning quite a bit from various sources online. However there is one thing that's really nagging me. Magnetic fields result from moving electrons. That indicates that a permanent magnet has...
  6. Eclair_de_XII

    Did Dropping My Vector Analysis Course Cost Me More Than Just Money?

    I dropped my vector analysis course from my fall semester because I couldn't do any of the homework without any outside help or from my professor, which made me think that I wouldn't be any good when taking any tests. Now, I'm deeply regretting this decision for two main reasons: (1) There are...
  7. K

    What does î(o) represent in vectors?

    This problem is fairly objective (though quite stupid) What does î(o) represent? Does it refer to a vector making angle 0 degrees with the x axis? I searched but couldn't find the answer anywhere. Please help. Moderator note: post edited and moved from hoemwork
  8. C

    B Stupid question of forces from one who skipped Physics B

    Sooooo yeah... My question is something very basic: Internal Forces vs External Forces. From my knowledge, Internal forces does not change the total mechanical energy while external does. But than why is gravity an internal force while normal force is external? Is there any other ways of...
  9. S

    Real estate seems like a stupid investment vehicle

    In the hottest of hot real estate markets you may see a house price go up 1x over 5 years and the owner may be able to capture 0.75x of that (after we subtract costs of property taxes, remodels, HOA dues, etc.). On the other hand, during a Bull Market in stocks there is the potential to for your...
  10. H

    Construction Can You Build a DIY Endless Pool for Under $1500?

    Hello, is this stupid? is this project possible, about 1,500 usd. I know the key is evenly distributed flow, so maybe two small motors. Maybe add a grate? this vid gave me this idea: thanks in advanced if anyone reads this thread
  11. S

    I Stupid question - how does fission bomb get initial neutron?

    OK, I understand the idea of neutron bombardment of fissile material causing the nuclei of this material to split, thereby releasing more than 1 neutron, which then go on to bombard other nuclei, such that if more than 1 neutron per reaction ends up causing further reactions, the rate of...
  12. danihel

    I My stupid question about particle-wave duality

    Again, my knowledge of quantum physics is so poor, I have no reference to give me any idea about the measure of stupidity of this question, so please bear with me.: Could it be that the nature of a ‘particle’ doesn’t change? That when decoherence occurs the wave function collapses into a new...
  13. Borg

    KISS Principle: Cleaning Up Code Left by Previous Programmer

    For the last week, I have been cleaning up code left by a previous programmer who clearly didn't know what the KISS principle was. I removed over 75 class files that were completely unnecessary and made the code ridiculously difficult for others to trace through. Most of this was code that...
  14. F

    I Find the Age of the Universe when Matter and Radiation densities were equal

    The universe is believed to be 13.8 billion years old and at least 45 billion light-years in radius. Now there is also a black hole at the center of our galaxy, with my basic understanding of black holes I understand that this would warp time and space, is it possible that it's warped so much...
  15. Noisy Rhysling

    How can a singularity be used to prevent the formation of the Moon?

    I have a race that is famous for going over the top with solutions to problems. Their garbage trucks dump the waste directly into their sun. Entire cities move around the globe to keep the sun at "high noon" ... so they don't have to light the streets at night. "Can openers" have self-contained...
  16. K. Doc Holiday

    B Answers to Beginner Questions about Black Hole Event Horizons

    I have searched the threads. Got some great insight but didn't find the answers to some of my questions Questions about Event Horizons Most of the textbooks and papers I have read no longer picture or talk about Einstein's original concept of a black hole; the Einstein - Rosen bridge. First...
  17. L

    I feel like I am very stupid and different from normal people

    Often when I ask questions in class, people laugh at them, so I stopped asking. What can I do? Am I more brain damanged than I think? I don't think university or any place is the place for me. I never see others or met others who talk or think like me, it makes me very angry and sad. Yesterday...
  18. T

    I Vacuum fluctuations - possible stupid question

    My background is in Health Physics and as such, I have had only rudimentary instruction in quantum mechanics, so my understanding (such as it is) is largely conceptual. With that in mind, this may be a very ignorant question, so I apologize in advance. I understand the theoretical basis for...
  19. smodak

    I Stupid question on index lowering and raising using metric

    Original Question (Please ignore this): I knew this when I read about it the first time a while back but can't put the two and two together anymore. :) I understand ##\vec{a_i}\centerdot \vec{a^j}=\delta_i^j## and ##g_{ij}=\vec{a_i}\centerdot\vec{a_j}## How does one get from there to...
  20. smodak

    I Stupid Question about a Notation in Linear algebra

    I know the arrow -> means a map. For example, defines a linear map. But I cannot figure out what does a X mean? I know that above denote a inner product map. whatever is on the left of the : is defined by whatever is on the right. but what is the x symbol? What is the correct way to read...
  21. B

    Is grading on a scale a flawed method for evaluating student performance?

    I have always thought that grading on a scale is stupid. When a teacher/professor grades tests based on a scale, the teacher grades each student based on their performance compared to other students. This is a stupid way to do things because it can both cause some students who know the...
  22. Robsta

    Stupid question about superposition of quantum states

    Homework Statement A quantum-mechanical harmonic oscillator with frequency ω has Hamiltonian eigenstates |n with eigenvalues En = (n + 1/2) ħω. Initially, the oscillator is in the state (|0> + |1>)/√2. Write down how the state of the oscillator evolves as a function of time t. Calculate the...
  23. I

    Impulse Engine (Drive) ....a stupid question?

    Recently, I've been watching a lot of those youtube videos debunking gyroscopic propulsion because everything about it violates the second law of motion or something... This got me thinking, if I was floating in space and I decided to swing a large rock on a rope around me, to generate some...
  24. G

    Understanding Skin Depth in DC and AC Fields: Confusion and Clarification

    Hello. The skin depth is nothing but measure of penetration depth of EM Wave when it is incident on the conductor. It is well known that the skin depth is decreased when the EM wave frequency increases. But thinking about DC field. We know that when DC is applied to metal (metal is installed...
  25. anton717

    Stupid questions physics majors might ask

    But what kind of energy does a particle possesses at 0 height?
  26. H

    Understanding Energy and Magnetism: Debunking Common Misconceptions

    I pry two magnets apart. The magnets attract each other. Say they exert a constant force F on each other. I exert an equivalent force F on each in the opposite direction and pull them apart a distance d (pull each of them d/2 distance). So I have done positive work Fd in total and increased the...
  27. C

    Business masters' with a ridiculously stupid question

    Please don't destroy me I'm utterly out of my league. Totally admit it. Never took a math class beyond college algebra (a proud, passing C) and no physics not even 101. Yes I suck. Ok so just intuiting but isn't distance always going to be a subjective measurement of space between...
  28. Y

    Math Help: Multiplying Zeq and I for Transformer - Quick and Easy Tips

    for transformer , Zeq multiply with I .. let say the Zeq is ( 0.140 + j 0.532 ) , while I is ( 8.7 /_ -36.87 ' ) A ... -36.87 is degree.. how to multiply these two things up? please help me . i m in urgent.. thanks.. please...
  29. ajlen

    Mybe stupid but i would like to know (vehicles in relative motion)

    So we have moving truck at 100mph, on truck is truck moving 100mph, then on this truck is truck moving 100mph, and on this truck is car moving 100mph. Then the last car is moving 400mph in space but only 300 from first truck?
  30. Borg

    Stupid Science Tricks: Improvising Toilet Shutoff Valve Repair

    Sometimes I just don't feel like doing it the right way and I 'improvise'. I can't be the only one who's done it so feel free to share your stories. Who knows - some of them might be useful to others. A few weeks ago, I had to replace the shutoff valve for a toilet. Of course, this required...
  31. M

    Trivial/pointless math puzzle I'm too stupid to solve

    Pretend you own a printing press and you want to be able to represent any arbitrarily large natural number. You also want to store the fewest possible number of characters in your collection, just to save space. What base, if any, would yield the largest ratio of numbers you can represent to...
  32. H

    Interstellar: A Visual Masterpiece with Disappointing Writing and Physics

    I saw "Interstellar"in IMAX. Fantastic visuals, but lazy dumb writing and very bad basic physics. Kip Thorne should be embarrassed to have is name so prominently associated with the movie.
  33. Danger

    Ridiculous Survey Questions: Exposing Mundane Attempts at Intelligence

    I've never been given a survey that didn't include at least half a dozen of those, but I'm specifically thinking of ones that Mundanes think make them seem intellectual while the choice of answers that they want you to choose from doesn't include the one that an intelligent person would give...
  34. Algr

    Calculating the Speed of a Space Dragon's Tail: Dr Who Episode Analysis

    Last week's Dr Who episode "Kill the Moon" infected me with stupid, and now I am compelled to try to calculate the speed at which the dragon wags it's tail. Observational data: 1) Earth's moon had grown to have Earth gravity at this point, so I am assuming that it was also the size of the Earth...
  35. Algr

    Embracing Stupidity: Exploring the Value of Asking 'Dumb' Questions

    Someone please ask a stupid question. I'm jealous of the people who can answer the smart ones.
  36. Q

    Help I'm feeling stupid. :( ("A solid sphere rolls down an incline)

    Homework Statement "A solid sphere rolls down an incline plane without slipping. If the center of mass of the sphere has a linear acceleration of 1.21 m/s2, what is the angle of the incline to the horizontal?" Homework Equations a = g * sin(θ) The Attempt at a Solution I got home...
  37. Borek

    World Cup - "soccer is boring and stupid" thread

    I don't want to derail the discussion in the WC threads, but after reading these two pages: http://www.anncoulter.com/columns/2014-06-25.html http://www.bbc.com/news/blogs-echochambers-28065500 I think it deserves its own thread. Bunch of thoughts: While I agree soccer can be boring...
  38. M

    Probably a stupid question regarding 4-dimensional space

    Okay, let me start this off by saying this, I have no idea what section this belongs in. On break between Spring and Summer classes, I stumbled upon a tesseract, or hypercube for the first time. And it got me thinking, on a purely philosophical level (ie, I have no where near the mathematical...
  39. L

    Efficient Prime Factoring Method for Numbers Below the Square Root"

    trust me this is trivial... As a kid I had a teacher fond of asking if numbers were prime. Of course at the time I had no calculator and did not have many primes remembered. I did not even know the less than square root. I came up with a method that made a simple chart of smaller than the...
  40. N

    Combining a Passion for Physics and Engineering: Possibilities and Opportunities

    I love physics and the advanced knowledge the field has, but I also love making applications and building things like engineers do. Would it be possible for me to get my undergraduate in physics, to get a masters in engineering (preferably electrical engineering) and then get a doctorate in...
  41. Borek

    Anti vaccine magazine (or how stupid people can get)

    Typically I don't post the same in more than one place, I will do it this time: http://www.pharmafile.com/news/181169/calls-end-uk-anti-vaccine-magazine Each time I hear about such things I think of the post mortem photography industry that existed at the end of 19th century...
  42. T

    Ways to Overcome Negative Signs in Math Problems | Expert Tips

    I'm getting tired of getting wrong answers and going back and doing them again and again only to find there's a negative sign in the problem I didn't see through the gigantic problem I just finished. If I were doing an actual classroom and not an online that doesn't allow shown work... I'd at...
  43. ABD EL HAMEED

    Am I the only one feeling dumb and stupid here? :p

    Am I the only one feeling dumb and stupid here?! :p Since I've joined this forum yesterday I've overwhelmed by the amount of info here and I felt kinda dumb really :/ I don't know if it's because everything I was taught was in Arabic or because I'm dumb or maybe just because I'm a normal 18...
  44. S

    Maximizing Math Success: Tips for Improving Study Habits and Skills

    Hi. I just came back from the registrar and dropped the complex analysis course I was failing. I don't think I slacked off. True, it's the summer and I had a few kickbacks with my friends that I wouldn't have had during the academic year, but I really wasn't doing much else besides complex...
  45. A

    An interesting(or very stupid) doubt that came to mind

    I was dealing with the derivation of Stefan's law from Planck's law. In this derivation one gets to the following equation \frac{xe^{x}}{e^{x}-1}=5 At this point most places I looked provide an aproximate numerical solution to this transcendental equation and carry on. But I wwas thinking...
  46. A

    Take Analysis concurrently with Proofs Course? Smart or Stupid Idea?

    Hi all. This is my first post on here. I come here to read what others ask/answer so this was the first place I thought of when this dilemma came up for me. I am a Math Major and I am for sure taking a proofs course this fall. I have been allowed to take Analysis concurrently with the proofs...
  47. cepheid

    Python Troubleshooting Nested Loops in Python: Unexpected Output Explained

    My code isn't working, and the reason seems to be because nested for loops in python don't work according to my expectations. If I have some code like this: f1 = open('name_of_file1.txt', 'r') f2 = open('name_of_file2.txt', 'r') for line1 in f1: #stuff at this level should happen...
  48. L

    Exploring the Charge of Methyl Anion: The Role of Unbonded Electrons

    Why does the Methyl anion have -1 charge when it has 2 unbonded electrons Why is it not -2?
  49. F

    Engineering Computer Engineering: Adapting to the Future of Technology

    We're hitting the silicon barrier so we might jump to a new type of computing, right? So would my knowledge all go to waste if we move to optical computing for example?
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