Test Definition and 1000 Threads

http://arxiv.org/abs/1401.6562 This looks very interesting, they are claiming a potential test for quantum gravity . What do we think?

So Thursday we had our first big test in class. I had managed to ace everything in the homework leading up to the test. I got cocky, and then I ended up bombing the test. I rushed through the test and completed it in about half the time I should have. The teacher offers a review with each...

This is technically a "homework" type question so I just need a bit of help. I'm just learning maple and writing a very basic procedure. I'm testing primality exhaustively by using the mod function. (Yes, maple has a built in procedure for this, but this is just an exercise). ISPRIME...

Homework Statement Question 1 Which statement is true of the coefficient of static friction? Answer It is the force resisting motion. It is proportional to the static friction force. It is a dimensionless quantity expressing the ratio of limiting friction to normal reaction...

Hey I've been lurking on this forum all day trying to find answers / help to problems I can't solve in my calculus text. So I finally got the bright idea to make an account and ask questions :) Although first I want to mention that I'm very rusty in math so I may need the special step by step...

Something I've wondered about the Double Slit Experiment is what happens to photons which fail to pass through either slit, and what is their behavior? Why not put some detectors on the source side of the slits during a double slit experiment to try to determine whether the photons are...

I just had a interview yesterday and found that every student must pass the swim test once they get into MIT, is this true? Is the swim test hard? What if I don't know how to swim at all? What should I do then?

Hello, I am posting this here becase this is not a homework, it;s just something I need to know. Please tell me what these two waveforms mean? I know that they're both lightning impulse waveform but what is the difference between those two, what gives them their shapes?

FDA examining antibacterial soaps, body washes http://www.cnn.com/2013/12/16/health/fda-antibacterial/

Hi there , I have two cast iron crankshafts for an engine I'm building , now even though they are similar in every way , made ofr the same engine etc etc, there is one thing I noticed different and it got my attention , I took a stainless steel screwdriver and hit each one of the cranks at...

I'm going to try my first chemistry experiment. http://www.chemteach.ac.nz/investigations/documents/chloride_mohr.pdf I bought 35g of potassium chromate and 5g of silver nitrate. 5g of silver nitrate is only enough for one test. What should I do with the silver afterwards? Is it...

I was searching the internet for information on Bell tests, when I found an article entitled "Taco Bell tests grilled stuffed nacho." Does anyone know how the stuffed nachos are used in Bell tests? http://www.huffingtonpost.com/2013/10/11/taco-bell-grilled-stuft-nacho_n_4086345.html...

**g_{ij} = ** **g^{ij} = ** **\Gamma_{ij}^{k} = ** <tex>R^{i}_{jkl} = </tex> <tex>R_{ij} = </tex> <tex>R = </tex> <tex>T_{ij} = </tex>

Homework Statement An incompressible fluid with density ρ is in a horizontal test tube of inner cross-sectional area A. The test tube spins in a horizontal circle in an ultracentrifuge at an angular speed ω. Gravitational forces are negligible. Consider a volume element of the fluid of area...

Hey guys. I am having some trouble visualizing one aspect of the Second derivative test in the 2 variable case (related to #3 below). Essentially, what does the curve look like when f_{xx}f_{yy} > 0, BUT f_{xx}f_{yy} < [f_{xy}]^{2}? To be more detailed, if the function is f(x,y), H(x,y) is the...

Homework Statement Does \sum_{n=1}^{\infty}a_n where a_n = \frac{(n+1)^{1/3}-n^{1/3}}{n} converge or diverge? Homework Equations The Attempt at a Solution The ratio test is inconclusive, as is the root test. The limit is equal to 0, but that doesn't say much. I've tried to find...

Hello, I'm creating a musical device which has stainless steel bars cut with a laser cutter. They are all the same length but vary in width. I created a set of test lengths (50 in total) and tested the pitch of each one using a tone analyzer. Now I'm looking to fit a curve to the data so...

Homework Statement Test the series for convergence or divergence Homework Equations A_n = Ʃ 1/(2+sin(k)) from k = 1 to ∞ The Attempt at a Solution I looked at this and I thought that sin(k) does not have a limit as k goes to infinity. So I was thinking that Lim k--> ∞ A_n =...

Homework Statement We threw a bunch of darts at a dart board to find the statistics of the positions. They ranged from -20 to 20 and the data is right here. ( each column corresponds to the dart number, it is just a syntax thing) The frequencies are below. Dart 1 Dart 2 Dart 3 Dart 4...

Homework Statement Homework Equations ƩMA = Ʃ r x F Total Force of x,y= 0 root(rx^2+ry^2)= Magnitude The Attempt at a Solution I cannot find i) my method 0=2000+3000(0.4)-Rc -3200N=-Rc(up) 0=3200-2000-3000+Ry Rx=1800 How to find to magnitude, when roller only got...

I'm getting a bit confused with the stats of a chi squared test, everyone in physics labs seems to use this as a test but I don't know why it's appropriate? My main question is how would I take a linear equation in say excel which has been fitted to a series of (x,y) data points (I do have...

Homework Statement http://i1345.photobucket.com/albums/p679/Duk_Bato/Untitled_zps84f60bfd.png Homework Equations ƩMA = Ʃ r x F The Attempt at a Solution 1.6 * T+ 0.8 * sin 40 *T = 1.2 * 250 T (1.6 + 0.8 * sin 40 ) = 300 T = 300 / ( 1.6 + 0.8 * sin 40 ) T = 141.9 N RX=...

Hi, I was wondering how I might make my own nitrate test strips. I am not really sure how/if they are any different from normal red/blue pH strips. I am looking for a way to compare nitrogen content in different soils. I know they make cheap kits, but I was hoping there was a way to do it...

I've got 3 problems that I got wrong on my most recent test (college 1st year physics). I need to figure out what I did wrong and hopefully someone here can help me. I know all my answers are wrong because I got marked wrong but I'm unsure why, or if there's another way or a better way to go...

Homework Statement Use the Limit Comparison Test to determine if the series converges or diverges: Ʃ (4/(7+4n(ln^2(n))) from n=1 to ∞. (The denominator, for clarity, in words is: seven plus 4n times the natural log squared of n.) Homework Equations Limit Comparison Test: Let Σa(n) be the...

Homework Statement This is what I understand about Alternating Series right now: If I have an alternate series, I can apply the alternative series test. \sum(-1)^{n}a_{n} Condition 1: Nth term test on a_{n} Condition 2: 0 < a_{n+1} ≤ a_{n}If condition 1 is positive or ∞, convergence is...

Homework Statement i am study for a physics test and i think my physics teacher gave me the wrong equation for shear stress Homework Equations she gave me F=Δx/l *A The Attempt at a Solution

Probably a stupid question but I'm not sure what to search for at this point. I'm trying to do a very simple diode test (half wave rectification I suppose it's called) using an ac source. The source is a 440hz signal off of my computer soundcard (generated and played via a .wave file). It's a...

Modern cell phones seems to come with IR filters on their cameras. I want to do an experiment to figure out what wavelengths these filters allow to pass and which they block. How would I go about doing this? Also, what sort of equipment would I need? I am a university student so I have access...

Hey all, The other day in O-Chem lab I tested trans-p-anisalacetophenone with the 2,4-dinitrophenylhydrazine test. I did not get the positive result that I expected. Is there any way someone could help me rationalize this? Would it have to do with the aromatic group in my compound? Did I...

I don't remember exactly how the question on my test was phrased but I believe it was phrased "Let A be an mxn matrix where m>n. Explain why in general there is not a solution to the equation Ax = b where b is a vector in Rm" This question was confusing to me because to me the meaning of...

There are 12 questions on an exam, and each student must answer 8 questions including at least 4 of the first 5 questions. How many different combinations of questions could a student choose to answer? So I got the number of ways a student can choose to answer the first 5 questions which is 6...

Homework Statement I'm designing a tyre test rig for a university project to measure camber, slip angle etc. An example of a test rig - http://www.ika.rwth-aachen.de/forschung/veroeffentlichung/1999/30.06.-02.07/im173g.gif Although my test rig will be for an RC car tyres, so not quite the...

Homework Statement Does the limit of (2y*x^2)/(4x^2-3y) exist as (x,y) -> (1,1)? If so what is the limit? The Attempt at a Solution So at first I thought I could just plug (1,1) into the equation and get two. My study buddy said that you have to make sure it approaches the same thing...

Hi, I will keep this short and sweet. I am drop testing an object of complicated geometry froma set height in 10 different orientations. Due to the complexity I decided to make a free falling rig where it slides (via roller bearings for example) when released. Simple freefall analysis...

Can the point to point test, (to determine the resistance between the main grounding system and all the major electrical frames, system neutral, etc) be made with an ordinary multimeter or does it need a special ground test tool? The NETA value of 0.5 ohm is widely accepted?

I see the open and closed circuit test on the transformer section I don't understand why we doing that(open and closed circuit test) can anyone explain and give some example?

Homework Statement determine whether the series (1-1/n^(1/3))^n converge or diverge Homework Equations all the testing procedure The Attempt at a Solution So I did the root test first, but the limit on the inside is 1. I then tried the ratio test but then when I tried taking the...

Homework Statement Use comparison test to see if the integral is convergent or divergent. Homework Equations integral [1,∞] (2+e^(-x))/x The Attempt at a Solution My books says that (1+e^(-x))/x is divergent and since my integral is bigger it is divergent also. TRUE OR...

Hi, I just took an IQ test, http://sifter.org/iqtest/ It relates the European IQ test to that of the Stanford-binet test. I just did it, but I was rather depressed and self-loathing, so maybe I could of done better... lol. I also was not aware of the time I was spending, perhaps better...

Over time I have realized that exams do not actually test intelligence (I can't define intelligence here but please bear with it). I'll take a specific example to explain this: - There are two people are I know, one of them always used to score more in math and the other less somehow. But the...

Homework Statement determine whether the Ʃ n4 / en2 is convergent or divergent? Homework Equations The Attempt at a Solution Using Root test: lim of n4/n / en as n approaches infinity But lim of n4/n as n approaches infinity = ∞0 So: Let N = lim of n4/n as n approaches...

I’m working with a Boolean parameter that has been proposed to identify good data and I want to test if it is effective on a data set where we know what is good (accurate) and bad (inaccurate results). The theory (sensu amplo!) behind the Boolean parameter, called “SC”, is that a value of “1”...

Homework Statement Ʃ cos(k*pi)/k from 1 to infinity. This is a test for convergence. and when is the proper time to use the alternating series test like using it on (-1)k(4k/8k) would result to divergence since lim of (4k/8k) is infinity and not 0 but the function is really convergent...

My textbook states that "For the integral test to apply, it is not necessary that f be always decreasing. What is important is that f be ultimately decreasing." I'm just curious what is meant by this statement. How do you define a function that is "ultimately decreasing"? It'd be great if you...

Is it possible to check the phase rotation sequence of a Medium Voltage Motor (Up to 6 kV) with one instrument? Does the shaft need to be moving while it is being tested? If instead of one, there are two motors electrically connected in parallel, with a common source feeder. will it be...

Homework Statement Test the following series for convergence or divergence. $$\sum_{n=1}^{\infty} \frac{1}{3^{\ln n}}$$ The Attempt at a Solution I've tried to compare this to geometric series ##3^n## but obviously the target term is larger overall than its geometric counterpart...

Homework Statement Preliminary test: If the terms of an infinite series do not tend to zero, the series diverges. In other words if ##\lim_{ n \to \infty}a_n \neq 0## then the series diverges. But if the limit is 0 we have to test further. Suppose a series a series satisfy this condition...

When performing a 2 hour pressure test on a waterline, the formula for calculating the allowable water loss over the 2 hours is given on the testing form. But, the form asks for the actual water loss. Of course, you know the pressure loss, but it asks for the water loss in gallons. This can...

If we have two sequences and the ratio of their limit is greater than zero, why does this mean that they either both converge or diverge? I don't understand why the test works. Also, what about lim[(1/x)/(1/x^2)] = lim x = ∞? The series of 1/x^2 converges but series of 1/x diverges...