Testing Definition and 589 Threads

A few weeks ago Physical Review published a Letter (an edited version of http://arxiv.org/abs/gr-qc/0702028" ) that says: "At this time, [Lunar Laser Rangefinding] provides the most precise test of [the gravitomagnetic phenomenon,..] likely better than the ultimate result from the GP-B...

I'm pretty embarassed that with a math degree I don't know how to do this. But today someone asked me to help him test this series for convergence: \Sigma \, ln(\dfrac{(k+1)^{2}}{k(k+2)} ) Maybe I'm just having a brain fart, but I can't think of any series to compare this to, and I...

Has anyone heard of this proposed test of string theory's extra dimensions? What do you think? Within the realm of reason? Doable within the next decade? Robert === http://www.news.wisc.edu/13422.html ...physicists at the University of Wisconsin-Madison have devised an approach...

Does anyone here know of a good circuit testing program that is free that includes diodes? I need to find certain voltages on specific points on a circuit, and I can't find anything good out there that can help.

Find the Limits1. lim 312 x->11+ 2. lim (x^2 +9)/(x^2 -1) x->1for #2 i got 10 as the answer, but I'm not sure if its right. Thanks edit: Sorry, wrong forum

I really don't understand hypothesis testing. How do I recognize which one is Ho and Ha in a problem? Is there a particular trick to facilitate my lfie?

Are there any experiments which test special relativity? I know of the Kennedy–Thorndike experiment, but it involves light. I am curious whether a different kind of experiments showing relativistic effects like time dilation or length contraction have been performed (I'm thinking of experiments...

For the function ## y=f(x) ## is there a test to prove if its roots are real or either has some complex roots?, or in more general cases: ## y=g(x)D^{k}f(x) ## k>0 and a real D=d/dx number.:rolleyes: :rolleyes: The question is that sometimes it can be very deceiving to tell if a function...

Need to know the test that will be performed on the following question: The data comprises hours devoted to patient care per week for practitioners in conventional and alternative medical practices. Question: Can we infer that the mean amount of time devoted to patient care per week by...

Hi, I am doing a small project on the "construction and control of a modern tensile testing machine" and am a bit unsure as to where to start on this! Does anyone have any ideas as to where I could find information on this subject, or know anything that might be helpful? Thanks, Chris

Dear all: I am a student at the University of Hartford and next semester I must take an Introductory physics course with basis on Calculus. Now I was pondering simply takeing a month or two and teaching it to myself and then testing out of the class so I can move onto more advanced...

how to test the component inside oxygen absorber in food?? we guess that there may be iron(II) or iron(III) ion. we use reducing agent or oxidzing agent to test it ? however, if both of them exist in the oxygen absorber, how can we distinguish them?? :confused:

Hello - I am working on a test for different neoprene mixtures. The set up is two jaws that clamp across the width of a strip of neoprene. One jaw is attached to a stationary post, the other is attached to a cylinder able to apply a variable pulling force. The problem I am having is...

I learned https://www.physicsforums.com/showthread.php?p=1098513&posted=1#post1098513" that some people are sensitive to lower frequency light than others. In fact, some people can see well into the infrared range. I was very skeptical, so I tested it out. I was right, I cannot see IR...

First and foremost, I am terrible in Stats so bear w/ me on this one. This is my question, if anyone has an idea on how to figure out this problem that would be great! Here it is: Suppose you flip a coin 100 times and you want to test the hypothesis that the coin is fair, making sure there is...

Please excuse my ignorance, but I could use some assistance. I need to get a device that will test if current can pass from an electrode through a connected wire on down to a pin that connects to a computer port. (Sometimes the electrical connection fails because of a poor connection between the...

Hi, my labmates and I are trying to fabricate a functional organic semiconductor; however we are having problems indicative of surace leakage between the gate and drain, or oxide breakdown (Fowler-Nordheim or otherwise). So now we're trying to test our silicon wafer without the organic...

I know they have tests where you can take the test and if you pass you don't have to take the course. I was wondering, if I educated myself enough on physics through books and videos as well as Math could I take tests to get credits for courses and get a degree froma college? cience and...

Hi, how do I test if a point is inside a triangle? The point is assumed to be in the triangle's plane.

http://arxiv.org/abs/astro-ph/0606641 Sorry link will not post abstract?

I have an interesting question: Could we simulate the solar array operating under sunlight, by covering the solar panel with dark paper and using a constant current source to pass rated current INTO the solar panel (e.g. using a bench power supply on constant current mode with a DC link...

Hi all, The system is RS422 and need a RS422-to-RS232 converter to download source from the system to the RS232 terminal. Question # 1: I usually use my laptop to test RS232 loopback. The laptop doesn't support RS422, so how to test to see if the RS422-to-RS232 is working...

x^2-6x-7/2x^2+3x +1

Hi,:cool: I really confuse about VOR circuit test of couse I mean for aviation, I want to know how is it working? If anyone has idea about that Please tell me.:frown: Thx a lot :rolleyes:

I'm having trouble with this problem Let n be a positive integer. Show that if the prime-power factorization of n-1 is n-1=(p1)^(a1)*(p2)^(a2)*...*(pt)^(at) , and for j=1,2,...,t, there exists an integer xj such that (xj)^(n-1)/(pj) is incongruent to 1(modn) and...

hi, I've just done an experinemt to try and show the resolution of the human eye in different light levels. i did it by putting a 0.25mm apart slits in a tube then, behind it had an adjustbable light, then i moved the slit further back, and asked them to say if they could see the two slits...

How do they test anmials intellgence?I herd of the resarch that dogs could do math,some langue and liture(I think).How do they test that.

Hello! Do you know any programs that can test randomness of pseudorandom sequences of real numbers?

I'm looking forward to doing some photography projects indoors, but I'm having a hard time differing between sources of light around me. I suspect that the lighting system in my basement is not as bright as I suspect it to be. Thus, I came to the conclusion that the upstairs room was a lot...

This is troubling, since the state and federal governements like to tout their successes in education. NY Times, Dec 16, 2005

I'm working on a problem that includes testing large numbers for primality. I'm using Pari/GP's built-in Baillie-PSW pseudoprimality test, but it (understandably!) runs slowly. I have some qustions, then: * I've been sieving the small prime factors from these numbers. For numbers if the...

Hi; Could someone please help me with this question: "Suppose you have measured the flow rate for a number of tubes with different lengths but the same radius, how would you graph your data to test Poiseulle's law (Hint: choose the scales of the axes so that the theoretical graph is a straight...

I want to know about knowing my DNA makeup. How can I get a skematic of my DNA and tell oll about me. Stuff like my racial makeup intelligence disease inherted things sexuality life expectancy traits habitual behavior strongpoints weaknesess.

Hi, My Question: Problem 1. The expected phenotypic ratios for each of the crosses below is 1:1. Determine whether the observed ratios are differ significantly (p < 0.05) from the expected. I used a Chi Square test to help me determine that answer and found the there is no probability of...

What I really need is an analogue function generator of some sort. Right now I am using a tektronix cfg250 which can put out up to 2mhz frequencies (square, sine, sawtooth, etc). Is there anything similar to this? I don't want anything with a screen on it...but it looks like tektronix doesn't...

I am a freshman in college with a double major. Most of what I know I am self taught in. I have talked to different professors about what courses I should take and some of them recommended taking courses that I already know. Some said to do this for an easy A and this does make sense. But others...

Hey, does anyone know a backyard method for testing adhesive strength? Need to compare the strength of things like sellotape/masking tape. Cheers A

Remember it is a very fine tunning job, and can all the inner and outter perturbances be damped out? i put my money on a null result.

Here's 2 more I am having difficulty with, I'll show you what I came up with or what I think the answer is 1. 2x = 3y^2 (sqrt 2x/3) = 3y/3 y = sqrt (2x/3) Symmetric to the X-axis 2. x^2 + 4y^2=16 not symmetric to any axis

I need help on some questions: The first two seem really easy, but i can't seem to figure out the right approach: Marks in ECMB11 are normally distributed with a mean of 70% and standard deviation of 10%. Suppose an A is a mark of 80% or more. 1. If you take a sample of 120 students, what...

I'm working though Introduction to Logic by Harry Gensler in which he presents his own invention for testing syllogisms-the star method. I was wondering how common this method is in comparison to Venn diagram methods. It's much quicker than Venn diagrams to use, but the beginning student is at a...

I am having trouble understanding the concept of the power of the test. Here is a sample question with solution: A company wants to test if average weekly demand is more than 2000 lbs. Test is to be carried out at 5% level of significance, and an estimate of the population variance is...

Hypothesis testing with normal distribution... I've been learning about Hypothesis testing with normal distribution, but I don't understand the need for the significance level. By this I mean that i understand that according to the Central Limit Theorem a distribution of the means will be a...

Hi all, I'm just curious what you see on these testimages: http://www.toledo-bend.com/colorblind/Ishihara.html http://en.wikipedia.org/wiki/Color_blindness When I was in school, our biology teacher asked us what we see and there were 2 out of 24 pupils who couldn't see the red 8. I...

http://arxiv.org/abs/astro-ph/0505267 Lorentz violation at high energy: concepts, phenomena and astrophysical constraints Ted Jacobson, Stefano Liberati, David Mattingly 56 pages, 3 figures, Invited article for Annals of Physics "We consider here the possibility of quantum gravity induced...

Let N be the number of flips of a coin up to an including the first flip of heads. Develope a significance test for N at the alpha=0.1 to test the hypothesis H that the coin is fair. Can someone please help me with this statistics problem? I have no clue how to start it. Thank you :smile:

\sum_{n=1}^\infty \frac{cos n}{n^2} Now, which test should i try? It doesn't appear to be anything straightforward like ratio test, comparison test etc and it's not a straightforward limit. cos(n) goes negative too, so that complicates things. Can anyone offer me any advice on a problem...

in all the failure theory we compare the stress in the structure to the yield stress in the uniaxial testing. How this is valid? for example in a structure the max normal stress is sigma x. and we compare this with the maximum normal stress in a uniaxial tension test. in vonmises also...

Test each of the following series for convergence by either the Comparison Test or the Limit Comparison Test. \sum_{n=1}^\infty \frac{2n^4}{n^5+7} this diverges using the p-series and comparison test right? p <1 \sum_{n=1}^\infty \frac{2n^4}{n^9+7} and this converges right? because p >...

We all know that Einsteins GTR accounts for observations that Newtonian gravitation cannot account for. I have "created" a theory of gravity (I put created in quotes becase it feels more like I found it) that makes corrections to Newtonian gravity in the same extreme relativistic cases. (this...